The base field set contains all fields which are at the root of the events. These fields are common across all types of events.
| Field | Description | Level |
|---|---|---|
Date/time when the event originated. This is the date/time extracted from the event, typically representing when the event was generated by the source. If the event source has no original timestamp, this value is typically populated by the first time the event was received by the pipeline. Required field for all events. type: date example: |
core |
|
Custom key/value pairs. Can be used to add meta information to events. Should not contain nested objects. All values are stored as keyword. Example: type: object example: |
core |
|
For log events the message field contains the log message, optimized for viewing in a log viewer. For structured logs without an original message field, other fields can be concatenated to form a human-readable summary of the event. If multiple messages exist, they can be combined into one message. type: text example: |
core |
|
List of keywords used to tag each event. type: keyword Note: this field should contain an array of values. example: |
core |
The agent fields contain the data about the software entity, if any, that collects, detects, or observes events on a host, or takes measurements on a host.
Examples include Beats. Agents may also run on observers. ECS agent.* fields shall be populated with details of the agent running on the host or observer where the event happened or the measurement was taken.
| Field | Description | Level |
|---|---|---|
Extended build information for the agent. This field is intended to contain any build information that a data source may provide, no specific formatting is required. type: keyword example: |
core |
|
Ephemeral identifier of this agent (if one exists). This id normally changes across restarts, but type: keyword example: |
extended |
|
Unique identifier of this agent (if one exists). Example: For Beats this would be beat.id. type: keyword example: |
core |
|
Custom name of the agent. This is a name that can be given to an agent. This can be helpful if for example two Filebeat instances are running on the same host but a human readable separation is needed on which Filebeat instance data is coming from. If no name is given, the name is often left empty. type: keyword example: |
core |
|
Type of the agent. The agent type always stays the same and should be given by the agent used. In case of Filebeat the agent would always be Filebeat also if two Filebeat instances are run on the same machine. type: keyword example: |
core |
|
Version of the agent. type: keyword example: |
core |
An autonomous system (AS) is a collection of connected Internet Protocol (IP) routing prefixes under the control of one or more network operators on behalf of a single administrative entity or domain that presents a common, clearly defined routing policy to the internet.
| Field | Description | Level |
|---|---|---|
Unique number allocated to the autonomous system. The autonomous system number (ASN) uniquely identifies each network on the Internet. type: long example: |
extended |
|
Organization name. type: keyword Multi-fields: * as.organization.name.text (type: text) example: |
extended |
The as fields are expected to be nested at: client.as, destination.as, server.as, source.as.
Note also that the as fields are not expected to be used directly at the root of the events.
A client is defined as the initiator of a network connection for events regarding sessions, connections, or bidirectional flow records.
For TCP events, the client is the initiator of the TCP connection that sends the SYN packet(s). For other protocols, the client is generally the initiator or requestor in the network transaction. Some systems use the term "originator" to refer the client in TCP connections. The client fields describe details about the system acting as the client in the network event. Client fields are usually populated in conjunction with server fields. Client fields are generally not populated for packet-level events.
Client / server representations can add semantic context to an exchange, which is helpful to visualize the data in certain situations. If your context falls in that category, you should still ensure that source and destination are filled appropriately.
| Field | Description | Level |
|---|---|---|
Some event client addresses are defined ambiguously. The event will sometimes list an IP, a domain or a unix socket. You should always store the raw address in the Then it should be duplicated to type: keyword |
extended |
|
Bytes sent from the client to the server. type: long example: |
core |
|
Client domain. type: keyword |
core |
|
IP address of the client (IPv4 or IPv6). type: ip |
core |
|
MAC address of the client. The notation format from RFC 7042 is suggested: Each octet (that is, 8-bit byte) is represented by two [uppercase] hexadecimal digits giving the value of the octet as an unsigned integer. Successive octets are separated by a hyphen. type: keyword example: |
core |
|
Translated IP of source based NAT sessions (e.g. internal client to internet). Typically connections traversing load balancers, firewalls, or routers. type: ip |
extended |
|
Translated port of source based NAT sessions (e.g. internal client to internet). Typically connections traversing load balancers, firewalls, or routers. type: long |
extended |
|
Packets sent from the client to the server. type: long example: |
core |
|
Port of the client. type: long |
core |
|
The highest registered client domain, stripped of the subdomain. For example, the registered domain for "foo.example.com" is "example.com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last two labels will not work well for TLDs such as "co.uk". type: keyword example: |
extended |
|
The subdomain portion of a fully qualified domain name includes all of the names except the host name under the registered_domain. In a partially qualified domain, or if the the qualification level of the full name cannot be determined, subdomain contains all of the names below the registered domain. For example the subdomain portion of "www.east.mydomain.co.uk" is "east". If the domain has multiple levels of subdomain, such as "sub2.sub1.example.com", the subdomain field should contain "sub2.sub1", with no trailing period. type: keyword example: |
extended |
|
The effective top level domain (eTLD), also known as the domain suffix, is the last part of the domain name. For example, the top level domain for example.com is "com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last label will not work well for effective TLDs such as "co.uk". type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
Fields describing an Autonomous System (Internet routing prefix). |
|
Fields describing a location. |
|
Fields to describe the user relevant to the event. |
Fields related to the cloud or infrastructure the events are coming from.
| Field | Description | Level |
|---|---|---|
The cloud account or organization id used to identify different entities in a multi-tenant environment. Examples: AWS account id, Google Cloud ORG Id, or other unique identifier. type: keyword example: |
extended |
|
The cloud account name or alias used to identify different entities in a multi-tenant environment. Examples: AWS account name, Google Cloud ORG display name. type: keyword example: |
extended |
|
Availability zone in which this host is running. type: keyword example: |
extended |
|
Instance ID of the host machine. type: keyword example: |
extended |
|
Instance name of the host machine. type: keyword |
extended |
|
Machine type of the host machine. type: keyword example: |
extended |
|
The cloud project identifier. Examples: Google Cloud Project id, Azure Project id. type: keyword example: |
extended |
|
The cloud project name. Examples: Google Cloud Project name, Azure Project name. type: keyword example: |
extended |
|
Name of the cloud provider. Example values are aws, azure, gcp, or digitalocean. type: keyword example: |
extended |
|
Region in which this host is running. type: keyword example: |
extended |
|
The cloud service name is intended to distinguish services running on different platforms within a provider, eg AWS EC2 vs Lambda, GCP GCE vs App Engine, Azure VM vs App Server. Examples: app engine, app service, cloud run, fargate, lambda. type: keyword example: |
extended |
These fields contain information about binary code signatures.
| Field | Description | Level |
|---|---|---|
Boolean to capture if a signature is present. type: boolean example: |
core |
|
The identifier used to sign the process. This is used to identify the application manufactured by a software vendor. The field is relevant to Apple *OS only. type: keyword example: |
extended |
|
Additional information about the certificate status. This is useful for logging cryptographic errors with the certificate validity or trust status. Leave unpopulated if the validity or trust of the certificate was unchecked. type: keyword example: |
extended |
|
Subject name of the code signer type: keyword example: |
core |
|
The team identifier used to sign the process. This is used to identify the team or vendor of a software product. The field is relevant to Apple *OS only. type: keyword example: |
extended |
|
Stores the trust status of the certificate chain. Validating the trust of the certificate chain may be complicated, and this field should only be populated by tools that actively check the status. type: boolean example: |
extended |
|
Boolean to capture if the digital signature is verified against the binary content. Leave unpopulated if a certificate was unchecked. type: boolean example: |
extended |
The code_signature fields are expected to be nested at: dll.code_signature, file.code_signature, process.code_signature.
Note also that the code_signature fields are not expected to be used directly at the root of the events.
Container fields are used for meta information about the specific container that is the source of information.
These fields help correlate data based containers from any runtime.
| Field | Description | Level |
|---|---|---|
Unique container id. type: keyword |
core |
|
Name of the image the container was built on. type: keyword |
extended |
|
Container image tags. type: keyword Note: this field should contain an array of values. |
extended |
|
Image labels. type: object |
extended |
|
Container name. type: keyword |
extended |
|
Runtime managing this container. type: keyword example: |
extended |
Destination fields capture details about the receiver of a network exchange/packet. These fields are populated from a network event, packet, or other event containing details of a network transaction.
Destination fields are usually populated in conjunction with source fields. The source and destination fields are considered the baseline and should always be filled if an event contains source and destination details from a network transaction. If the event also contains identification of the client and server roles, then the client and server fields should also be populated.
| Field | Description | Level |
|---|---|---|
Some event destination addresses are defined ambiguously. The event will sometimes list an IP, a domain or a unix socket. You should always store the raw address in the Then it should be duplicated to type: keyword |
extended |
|
Bytes sent from the destination to the source. type: long example: |
core |
|
Destination domain. type: keyword |
core |
|
IP address of the destination (IPv4 or IPv6). type: ip |
core |
|
MAC address of the destination. The notation format from RFC 7042 is suggested: Each octet (that is, 8-bit byte) is represented by two [uppercase] hexadecimal digits giving the value of the octet as an unsigned integer. Successive octets are separated by a hyphen. type: keyword example: |
core |
|
Translated ip of destination based NAT sessions (e.g. internet to private DMZ) Typically used with load balancers, firewalls, or routers. type: ip |
extended |
|
Port the source session is translated to by NAT Device. Typically used with load balancers, firewalls, or routers. type: long |
extended |
|
Packets sent from the destination to the source. type: long example: |
core |
|
Port of the destination. type: long |
core |
|
The highest registered destination domain, stripped of the subdomain. For example, the registered domain for "foo.example.com" is "example.com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last two labels will not work well for TLDs such as "co.uk". type: keyword example: |
extended |
|
The subdomain portion of a fully qualified domain name includes all of the names except the host name under the registered_domain. In a partially qualified domain, or if the the qualification level of the full name cannot be determined, subdomain contains all of the names below the registered domain. For example the subdomain portion of "www.east.mydomain.co.uk" is "east". If the domain has multiple levels of subdomain, such as "sub2.sub1.example.com", the subdomain field should contain "sub2.sub1", with no trailing period. type: keyword example: |
extended |
|
The effective top level domain (eTLD), also known as the domain suffix, is the last part of the domain name. For example, the top level domain for example.com is "com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last label will not work well for effective TLDs such as "co.uk". type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
Fields describing an Autonomous System (Internet routing prefix). |
|
Fields describing a location. |
|
Fields to describe the user relevant to the event. |
These fields contain information about code libraries dynamically loaded into processes.
Many operating systems refer to "shared code libraries" with different names, but this field set refers to all of the following:
-
Dynamic-link library (
.dll) commonly used on Windows -
Shared Object (
.so) commonly used on Unix-like operating systems -
Dynamic library (
.dylib) commonly used on macOS
| Field | Description | Level |
|---|---|---|
Name of the library. This generally maps to the name of the file on disk. type: keyword example: |
core |
|
Full file path of the library. type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
These fields contain information about binary code signatures. |
|
Hashes, usually file hashes. |
|
These fields contain Windows Portable Executable (PE) metadata. |
Fields describing DNS queries and answers.
DNS events should either represent a single DNS query prior to getting answers (dns.type:query) or they should represent a full exchange and contain the query details as well as all of the answers that were provided for this query (dns.type:answer).
| Field | Description | Level |
|---|---|---|
An array containing an object for each answer section returned by the server. The main keys that should be present in these objects are defined by ECS. Records that have more information may contain more keys than what ECS defines. Not all DNS data sources give all details about DNS answers. At minimum, answer objects must contain the type: object Note: this field should contain an array of values. |
extended |
|
The class of DNS data contained in this resource record. type: keyword example: |
extended |
|
The data describing the resource. The meaning of this data depends on the type and class of the resource record. type: keyword example: |
extended |
|
The domain name to which this resource record pertains. If a chain of CNAME is being resolved, each answer’s type: keyword example: |
extended |
|
The time interval in seconds that this resource record may be cached before it should be discarded. Zero values mean that the data should not be cached. type: long example: |
extended |
|
The type of data contained in this resource record. type: keyword example: |
extended |
|
Array of 2 letter DNS header flags. Expected values are: AA, TC, RD, RA, AD, CD, DO. type: keyword Note: this field should contain an array of values. example: |
extended |
|
The DNS packet identifier assigned by the program that generated the query. The identifier is copied to the response. type: keyword example: |
extended |
|
The DNS operation code that specifies the kind of query in the message. This value is set by the originator of a query and copied into the response. type: keyword example: |
extended |
|
The class of records being queried. type: keyword example: |
extended |
|
The name being queried. If the name field contains non-printable characters (below 32 or above 126), those characters should be represented as escaped base 10 integers (\DDD). Back slashes and quotes should be escaped. Tabs, carriage returns, and line feeds should be converted to \t, \r, and \n respectively. type: keyword example: |
extended |
|
The highest registered domain, stripped of the subdomain. For example, the registered domain for "foo.example.com" is "example.com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last two labels will not work well for TLDs such as "co.uk". type: keyword example: |
extended |
|
The subdomain is all of the labels under the registered_domain. If the domain has multiple levels of subdomain, such as "sub2.sub1.example.com", the subdomain field should contain "sub2.sub1", with no trailing period. type: keyword example: |
extended |
|
The effective top level domain (eTLD), also known as the domain suffix, is the last part of the domain name. For example, the top level domain for example.com is "com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last label will not work well for effective TLDs such as "co.uk". type: keyword example: |
extended |
|
The type of record being queried. type: keyword example: |
extended |
|
Array containing all IPs seen in The type: ip Note: this field should contain an array of values. example: |
extended |
|
The DNS response code. type: keyword example: |
extended |
|
The type of DNS event captured, query or answer. If your source of DNS events only gives you DNS queries, you should only create dns events of type If your source of DNS events gives you answers as well, you should create one event per query (optionally as soon as the query is seen). And a second event containing all query details as well as an array of answers. type: keyword example: |
extended |
Meta-information specific to ECS.
| Field | Description | Level |
|---|---|---|
ECS version this event conforms to. When querying across multiple indices — which may conform to slightly different ECS versions — this field lets integrations adjust to the schema version of the events. type: keyword example: |
core |
These fields can represent errors of any kind.
Use them for errors that happen while fetching events or in cases where the event itself contains an error.
| Field | Description | Level |
|---|---|---|
Error code describing the error. type: keyword |
core |
|
Unique identifier for the error. type: keyword |
core |
|
Error message. type: text |
core |
|
The stack trace of this error in plain text. type: keyword Multi-fields: * error.stack_trace.text (type: text) |
extended |
|
The type of the error, for example the class name of the exception. type: keyword example: |
extended |
The event fields are used for context information about the log or metric event itself.
A log is defined as an event containing details of something that happened. Log events must include the time at which the thing happened. Examples of log events include a process starting on a host, a network packet being sent from a source to a destination, or a network connection between a client and a server being initiated or closed. A metric is defined as an event containing one or more numerical measurements and the time at which the measurement was taken. Examples of metric events include memory pressure measured on a host and device temperature. See the event.kind definition in this section for additional details about metric and state events.
| Field | Description | Level |
|---|---|---|
The action captured by the event. This describes the information in the event. It is more specific than type: keyword example: |
core |
|
This is one of four ECS Categorization Fields, and indicates the second level in the ECS category hierarchy.
This field is an array. This will allow proper categorization of some events that fall in multiple categories. type: keyword Note: this field should contain an array of values. Important: The field value must be one of the following: authentication, configuration, database, driver, file, host, iam, intrusion_detection, malware, network, package, process, registry, session, web To learn more about when to use which value, visit the page allowed values for event.category |
core |
|
Identification code for this event, if one exists. Some event sources use event codes to identify messages unambiguously, regardless of message language or wording adjustments over time. An example of this is the Windows Event ID. type: keyword example: |
extended |
|
event.created contains the date/time when the event was first read by an agent, or by your pipeline. This field is distinct from @timestamp in that @timestamp typically contain the time extracted from the original event. In most situations, these two timestamps will be slightly different. The difference can be used to calculate the delay between your source generating an event, and the time when your agent first processed it. This can be used to monitor your agent’s or pipeline’s ability to keep up with your event source. In case the two timestamps are identical, @timestamp should be used. type: date example: |
core |
|
Name of the dataset. If an event source publishes more than one type of log or events (e.g. access log, error log), the dataset is used to specify which one the event comes from. It’s recommended but not required to start the dataset name with the module name, followed by a dot, then the dataset name. type: keyword example: |
core |
|
Duration of the event in nanoseconds. If event.start and event.end are known this value should be the difference between the end and start time. type: long |
core |
|
event.end contains the date when the event ended or when the activity was last observed. type: date |
extended |
|
Hash (perhaps logstash fingerprint) of raw field to be able to demonstrate log integrity. type: keyword example: |
extended |
|
Unique ID to describe the event. type: keyword example: |
core |
|
Timestamp when an event arrived in the central data store. This is different from In normal conditions, assuming no tampering, the timestamps should chronologically look like this: type: date example: |
core |
|
This is one of four ECS Categorization Fields, and indicates the highest level in the ECS category hierarchy.
The value of this field can be used to inform how these kinds of events should be handled. They may warrant different retention, different access control, it may also help understand whether the data coming in at a regular interval or not. type: keyword Important: The field value must be one of the following: alert, event, metric, state, pipeline_error, signal To learn more about when to use which value, visit the page allowed values for event.kind |
core |
|
Name of the module this data is coming from. If your monitoring agent supports the concept of modules or plugins to process events of a given source (e.g. Apache logs), type: keyword example: |
core |
|
Raw text message of entire event. Used to demonstrate log integrity. This field is not indexed and doc_values are disabled. It cannot be searched, but it can be retrieved from type: keyword example: |
core |
|
This is one of four ECS Categorization Fields, and indicates the lowest level in the ECS category hierarchy.
Note that when a single transaction is described in multiple events, each event may populate different values of Also note that in the case of a compound event (a single event that contains multiple logical events), this field should be populated with the value that best captures the overall success or failure from the perspective of the event producer. Further note that not all events will have an associated outcome. For example, this field is generally not populated for metric events, events with type: keyword Important: The field value must be one of the following: failure, success, unknown To learn more about when to use which value, visit the page allowed values for event.outcome |
core |
|
Source of the event. Event transports such as Syslog or the Windows Event Log typically mention the source of an event. It can be the name of the software that generated the event (e.g. Sysmon, httpd), or of a subsystem of the operating system (kernel, Microsoft-Windows-Security-Auditing). type: keyword example: |
extended |
|
Reason why this event happened, according to the source. This describes the why of a particular action or outcome captured in the event. Where type: keyword example: |
extended |
|
Reference URL linking to additional information about this event. This URL links to a static definition of this event. Alert events, indicated by type: keyword |
extended |
|
Risk score or priority of the event (e.g. security solutions). Use your system’s original value here. type: float |
core |
|
Normalized risk score or priority of the event, on a scale of 0 to 100. This is mainly useful if you use more than one system that assigns risk scores, and you want to see a normalized value across all systems. type: float |
extended |
|
Sequence number of the event. The sequence number is a value published by some event sources, to make the exact ordering of events unambiguous, regardless of the timestamp precision. type: long |
extended |
|
The numeric severity of the event according to your event source. What the different severity values mean can be different between sources and use cases. It’s up to the implementer to make sure severities are consistent across events from the same source. The Syslog severity belongs in type: long example: |
core |
|
event.start contains the date when the event started or when the activity was first observed. type: date |
extended |
|
This field should be populated when the event’s timestamp does not include timezone information already (e.g. default Syslog timestamps). It’s optional otherwise. Acceptable timezone formats are: a canonical ID (e.g. "Europe/Amsterdam"), abbreviated (e.g. "EST") or an HH:mm differential (e.g. "-05:00"). type: keyword |
extended |
|
This is one of four ECS Categorization Fields, and indicates the third level in the ECS category hierarchy.
This field is an array. This will allow proper categorization of some events that fall in multiple event types. type: keyword Note: this field should contain an array of values. Important: The field value must be one of the following: access, admin, allowed, change, connection, creation, deletion, denied, end, error, group, info, installation, protocol, start, user To learn more about when to use which value, visit the page allowed values for event.type |
core |
|
URL linking to an external system to continue investigation of this event. This URL links to another system where in-depth investigation of the specific occurrence of this event can take place. Alert events, indicated by type: keyword example: |
extended |
A file is defined as a set of information that has been created on, or has existed on a filesystem.
File objects can be associated with host events, network events, and/or file events (e.g., those produced by File Integrity Monitoring [FIM] products or services). File fields provide details about the affected file associated with the event or metric.
| Field | Description | Level |
|---|---|---|
Last time the file was accessed. Note that not all filesystems keep track of access time. type: date |
extended |
|
Array of file attributes. Attributes names will vary by platform. Here’s a non-exhaustive list of values that are expected in this field: archive, compressed, directory, encrypted, execute, hidden, read, readonly, system, write. type: keyword Note: this field should contain an array of values. example: |
extended |
|
File creation time. Note that not all filesystems store the creation time. type: date |
extended |
|
Last time the file attributes or metadata changed. Note that changes to the file content will update type: date |
extended |
|
Device that is the source of the file. type: keyword example: |
extended |
|
Directory where the file is located. It should include the drive letter, when appropriate. type: keyword example: |
extended |
|
Drive letter where the file is located. This field is only relevant on Windows. The value should be uppercase, and not include the colon. type: keyword example: |
extended |
|
File extension, excluding the leading dot. Note that when the file name has multiple extensions (example.tar.gz), only the last one should be captured ("gz", not "tar.gz"). type: keyword example: |
extended |
|
Primary group ID (GID) of the file. type: keyword example: |
extended |
|
Primary group name of the file. type: keyword example: |
extended |
|
Inode representing the file in the filesystem. type: keyword example: |
extended |
|
MIME type should identify the format of the file or stream of bytes using IANA official types, where possible. When more than one type is applicable, the most specific type should be used. type: keyword |
extended |
|
Mode of the file in octal representation. type: keyword example: |
extended |
|
Last time the file content was modified. type: date |
extended |
|
Name of the file including the extension, without the directory. type: keyword example: |
extended |
|
File owner’s username. type: keyword example: |
extended |
|
Full path to the file, including the file name. It should include the drive letter, when appropriate. type: keyword Multi-fields: * file.path.text (type: text) example: |
extended |
|
File size in bytes. Only relevant when type: long example: |
extended |
|
Target path for symlinks. type: keyword Multi-fields: * file.target_path.text (type: text) |
extended |
|
File type (file, dir, or symlink). type: keyword example: |
extended |
|
The user ID (UID) or security identifier (SID) of the file owner. type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
These fields contain information about binary code signatures. |
|
Hashes, usually file hashes. |
|
These fields contain Windows Portable Executable (PE) metadata. |
|
These fields contain x509 certificate metadata. |
Geo fields can carry data about a specific location related to an event.
This geolocation information can be derived from techniques such as Geo IP, or be user-supplied.
| Field | Description | Level |
|---|---|---|
City name. type: keyword example: |
core |
|
Two-letter code representing continent’s name. type: keyword example: |
core |
|
Name of the continent. type: keyword example: |
core |
|
Country ISO code. type: keyword example: |
core |
|
Country name. type: keyword example: |
core |
|
Longitude and latitude. type: geo_point example: |
core |
|
User-defined description of a location, at the level of granularity they care about. Could be the name of their data centers, the floor number, if this describes a local physical entity, city names. Not typically used in automated geolocation. type: keyword example: |
extended |
|
Postal code associated with the location. Values appropriate for this field may also be known as a postcode or ZIP code and will vary widely from country to country. type: keyword example: |
core |
|
Region ISO code. type: keyword example: |
core |
|
Region name. type: keyword example: |
core |
|
The time zone of the location, such as IANA time zone name. type: keyword example: |
core |
The geo fields are expected to be nested at: client.geo, destination.geo, host.geo, observer.geo, server.geo, source.geo.
Note also that the geo fields are not expected to be used directly at the root of the events.
The group fields are meant to represent groups that are relevant to the event.
| Field | Description | Level |
|---|---|---|
Name of the directory the group is a member of. For example, an LDAP or Active Directory domain name. type: keyword |
extended |
|
Unique identifier for the group on the system/platform. type: keyword |
extended |
|
Name of the group. type: keyword |
extended |
The group fields are expected to be nested at: user.group.
Note also that the group fields may be used directly at the root of the events.
The hash fields represent different bitwise hash algorithms and their values.
Field names for common hashes (e.g. MD5, SHA1) are predefined. Add fields for other hashes by lowercasing the hash algorithm name and using underscore separators as appropriate (snake case, e.g. sha3_512).
Note that this fieldset is used for common hashes that may be computed over a range of generic bytes. Entity-specific hashes such as ja3 or imphash are placed in the fieldsets to which they relate (tls and pe, respectively).
| Field | Description | Level |
|---|---|---|
MD5 hash. type: keyword |
extended |
|
SHA1 hash. type: keyword |
extended |
|
SHA256 hash. type: keyword |
extended |
|
SHA512 hash. type: keyword |
extended |
|
SSDEEP hash. type: keyword |
extended |
The hash fields are expected to be nested at: dll.hash, file.hash, process.hash.
Note also that the hash fields are not expected to be used directly at the root of the events.
A host is defined as a general computing instance.
ECS host.* fields should be populated with details about the host on which the event happened, or from which the measurement was taken. Host types include hardware, virtual machines, Docker containers, and Kubernetes nodes.
| Field | Description | Level |
|---|---|---|
Operating system architecture. type: keyword example: |
core |
|
beta:[ This field is currently considered beta. ] Percent CPU used which is normalized by the number of CPU cores and it ranges from 0 to 1. Scaling factor: 1000. For example: For a two core host, this value should be the average of the two cores, between 0 and 1. type: scaled_float |
extended |
|
beta:[ This field is currently considered beta. ] The total number of bytes (gauge) read successfully (aggregated from all disks) since the last metric collection. type: long |
extended |
|
beta:[ This field is currently considered beta. ] The total number of bytes (gauge) written successfully (aggregated from all disks) since the last metric collection. type: long |
extended |
|
Name of the domain of which the host is a member. For example, on Windows this could be the host’s Active Directory domain or NetBIOS domain name. For Linux this could be the domain of the host’s LDAP provider. type: keyword example: |
extended |
|
Hostname of the host. It normally contains what the type: keyword |
core |
|
Unique host id. As hostname is not always unique, use values that are meaningful in your environment. Example: The current usage of type: keyword |
core |
|
Host ip addresses. type: ip Note: this field should contain an array of values. |
core |
|
Host MAC addresses. The notation format from RFC 7042 is suggested: Each octet (that is, 8-bit byte) is represented by two [uppercase] hexadecimal digits giving the value of the octet as an unsigned integer. Successive octets are separated by a hyphen. type: keyword Note: this field should contain an array of values. example: |
core |
|
Name of the host. It can contain what type: keyword |
core |
|
beta:[ This field is currently considered beta. ] The number of bytes (gauge) sent out on all network interfaces by the host since the last metric collection. type: long |
extended |
|
beta:[ This field is currently considered beta. ] The number of packets (gauge) sent out on all network interfaces by the host since the last metric collection. type: long |
extended |
|
beta:[ This field is currently considered beta. ] The number of bytes received (gauge) on all network interfaces by the host since the last metric collection. type: long |
extended |
|
beta:[ This field is currently considered beta. ] The number of packets (gauge) received on all network interfaces by the host since the last metric collection. type: long |
extended |
|
Type of host. For Cloud providers this can be the machine type like type: keyword |
core |
|
Seconds the host has been up. type: long example: |
extended |
| Nested fields | Description |
|---|---|
Fields describing a location. |
|
OS fields contain information about the operating system. |
|
Fields to describe the user relevant to the event. |
Fields related to HTTP activity. Use the url field set to store the url of the request.
| Field | Description | Level |
|---|---|---|
Size in bytes of the request body. type: long example: |
extended |
|
The full HTTP request body. type: keyword Multi-fields: * http.request.body.content.text (type: text) example: |
extended |
|
Total size in bytes of the request (body and headers). type: long example: |
extended |
|
A unique identifier for each HTTP request to correlate logs between clients and servers in transactions. The id may be contained in a non-standard HTTP header, such as type: keyword example: |
extended |
|
HTTP request method. Prior to ECS 1.6.0 the following guidance was provided: "The field value must be normalized to lowercase for querying." As of ECS 1.6.0, the guidance is deprecated because the original case of the method may be useful in anomaly detection. Original case will be mandated in ECS 2.0.0 type: keyword example: |
extended |
|
Mime type of the body of the request. This value must only be populated based on the content of the request body, not on the type: keyword example: |
extended |
|
Referrer for this HTTP request. type: keyword example: |
extended |
|
Size in bytes of the response body. type: long example: |
extended |
|
The full HTTP response body. type: keyword Multi-fields: * http.response.body.content.text (type: text) example: |
extended |
|
Total size in bytes of the response (body and headers). type: long example: |
extended |
|
Mime type of the body of the response. This value must only be populated based on the content of the response body, not on the type: keyword example: |
extended |
|
HTTP response status code. type: long example: |
extended |
|
HTTP version. type: keyword example: |
extended |
The interface fields are used to record ingress and egress interface information when reported by an observer (e.g. firewall, router, load balancer) in the context of the observer handling a network connection. In the case of a single observer interface (e.g. network sensor on a span port) only the observer.ingress information should be populated.
| Field | Description | Level |
|---|---|---|
Interface alias as reported by the system, typically used in firewall implementations for e.g. inside, outside, or dmz logical interface naming. type: keyword example: |
extended |
|
Interface ID as reported by an observer (typically SNMP interface ID). type: keyword example: |
extended |
|
Interface name as reported by the system. type: keyword example: |
extended |
The interface fields are expected to be nested at: observer.egress.interface, observer.ingress.interface.
Note also that the interface fields are not expected to be used directly at the root of the events.
Details about the event’s logging mechanism or logging transport.
The log.* fields are typically populated with details about the logging mechanism used to create and/or transport the event. For example, syslog details belong under log.syslog.*.
The details specific to your event source are typically not logged under log., but rather in event. or in other ECS fields.
| Field | Description | Level |
|---|---|---|
Full path to the log file this event came from, including the file name. It should include the drive letter, when appropriate. If the event wasn’t read from a log file, do not populate this field. type: keyword example: |
extended |
|
Original log level of the log event. If the source of the event provides a log level or textual severity, this is the one that goes in Some examples are type: keyword example: |
core |
|
The name of the logger inside an application. This is usually the name of the class which initialized the logger, or can be a custom name. type: keyword example: |
core |
|
The line number of the file containing the source code which originated the log event. type: integer example: |
extended |
|
The name of the file containing the source code which originated the log event. Note that this field is not meant to capture the log file. The correct field to capture the log file is type: keyword example: |
extended |
|
The name of the function or method which originated the log event. type: keyword example: |
extended |
|
This is the original log message and contains the full log message before splitting it up in multiple parts. In contrast to the This field is not indexed and doc_values are disabled so it can’t be queried but the value can be retrieved from type: keyword example: |
core |
|
The Syslog metadata of the event, if the event was transmitted via Syslog. Please see RFCs 5424 or 3164. type: object |
extended |
|
The Syslog numeric facility of the log event, if available. According to RFCs 5424 and 3164, this value should be an integer between 0 and 23. type: long example: |
extended |
|
The Syslog text-based facility of the log event, if available. type: keyword example: |
extended |
|
Syslog numeric priority of the event, if available. According to RFCs 5424 and 3164, the priority is 8 * facility + severity. This number is therefore expected to contain a value between 0 and 191. type: long example: |
extended |
|
The Syslog numeric severity of the log event, if available. If the event source publishing via Syslog provides a different numeric severity value (e.g. firewall, IDS), your source’s numeric severity should go to type: long example: |
extended |
|
The Syslog numeric severity of the log event, if available. If the event source publishing via Syslog provides a different severity value (e.g. firewall, IDS), your source’s text severity should go to type: keyword example: |
extended |
The network is defined as the communication path over which a host or network event happens.
The network.* fields should be populated with details about the network activity associated with an event.
| Field | Description | Level |
|---|---|---|
A name given to an application level protocol. This can be arbitrarily assigned for things like microservices, but also apply to things like skype, icq, facebook, twitter. This would be used in situations where the vendor or service can be decoded such as from the source/dest IP owners, ports, or wire format. The field value must be normalized to lowercase for querying. See the documentation section "Implementing ECS". type: keyword example: |
extended |
|
Total bytes transferred in both directions. If type: long example: |
core |
|
A hash of source and destination IPs and ports, as well as the protocol used in a communication. This is a tool-agnostic standard to identify flows. Learn more at https://github.com/corelight/community-id-spec. type: keyword example: |
extended |
|
Direction of the network traffic. Recommended values are: * ingress * egress * inbound * outbound * internal * external * unknown When mapping events from a host-based monitoring context, populate this field from the host’s point of view, using the values "ingress" or "egress". When mapping events from a network or perimeter-based monitoring context, populate this field from the point of view of the network perimeter, using the values "inbound", "outbound", "internal" or "external". Note that "internal" is not crossing perimeter boundaries, and is meant to describe communication between two hosts within the perimeter. Note also that "external" is meant to describe traffic between two hosts that are external to the perimeter. This could for example be useful for ISPs or VPN service providers. type: keyword example: |
core |
|
Host IP address when the source IP address is the proxy. type: ip example: |
core |
|
IANA Protocol Number (https://www.iana.org/assignments/protocol-numbers/protocol-numbers.xhtml). Standardized list of protocols. This aligns well with NetFlow and sFlow related logs which use the IANA Protocol Number. type: keyword example: |
extended |
|
Network.inner fields are added in addition to network.vlan fields to describe the innermost VLAN when q-in-q VLAN tagging is present. Allowed fields include vlan.id and vlan.name. Inner vlan fields are typically used when sending traffic with multiple 802.1q encapsulations to a network sensor (e.g. Zeek, Wireshark.) type: object |
extended |
|
Name given by operators to sections of their network. type: keyword example: |
extended |
|
Total packets transferred in both directions. If type: long example: |
core |
|
L7 Network protocol name. ex. http, lumberjack, transport protocol. The field value must be normalized to lowercase for querying. See the documentation section "Implementing ECS". type: keyword example: |
core |
|
Same as network.iana_number, but instead using the Keyword name of the transport layer (udp, tcp, ipv6-icmp, etc.) The field value must be normalized to lowercase for querying. See the documentation section "Implementing ECS". type: keyword example: |
core |
|
In the OSI Model this would be the Network Layer. ipv4, ipv6, ipsec, pim, etc The field value must be normalized to lowercase for querying. See the documentation section "Implementing ECS". type: keyword example: |
core |
| Nested fields | Description |
|---|---|
Fields to describe observed VLAN information. |
|
Fields to describe observed VLAN information. |
An observer is defined as a special network, security, or application device used to detect, observe, or create network, security, or application-related events and metrics.
This could be a custom hardware appliance or a server that has been configured to run special network, security, or application software. Examples include firewalls, web proxies, intrusion detection/prevention systems, network monitoring sensors, web application firewalls, data loss prevention systems, and APM servers. The observer.* fields shall be populated with details of the system, if any, that detects, observes and/or creates a network, security, or application event or metric. Message queues and ETL components used in processing events or metrics are not considered observers in ECS.
| Field | Description | Level |
|---|---|---|
Observer.egress holds information like interface number and name, vlan, and zone information to classify egress traffic. Single armed monitoring such as a network sensor on a span port should only use observer.ingress to categorize traffic. type: object |
extended |
|
Network zone of outbound traffic as reported by the observer to categorize the destination area of egress traffic, e.g. Internal, External, DMZ, HR, Legal, etc. type: keyword example: |
extended |
|
Hostname of the observer. type: keyword |
core |
|
Observer.ingress holds information like interface number and name, vlan, and zone information to classify ingress traffic. Single armed monitoring such as a network sensor on a span port should only use observer.ingress to categorize traffic. type: object |
extended |
|
Network zone of incoming traffic as reported by the observer to categorize the source area of ingress traffic. e.g. internal, External, DMZ, HR, Legal, etc. type: keyword example: |
extended |
|
IP addresses of the observer. type: ip Note: this field should contain an array of values. |
core |
|
MAC addresses of the observer. The notation format from RFC 7042 is suggested: Each octet (that is, 8-bit byte) is represented by two [uppercase] hexadecimal digits giving the value of the octet as an unsigned integer. Successive octets are separated by a hyphen. type: keyword Note: this field should contain an array of values. example: |
core |
|
Custom name of the observer. This is a name that can be given to an observer. This can be helpful for example if multiple firewalls of the same model are used in an organization. If no custom name is needed, the field can be left empty. type: keyword example: |
extended |
|
The product name of the observer. type: keyword example: |
extended |
|
Observer serial number. type: keyword |
extended |
|
The type of the observer the data is coming from. There is no predefined list of observer types. Some examples are type: keyword example: |
core |
|
Vendor name of the observer. type: keyword example: |
core |
|
Observer version. type: keyword |
core |
| Nested fields | Description |
|---|---|
Fields to describe observer interface information. |
|
Fields to describe observed VLAN information. |
|
Fields describing a location. |
|
Fields to describe observer interface information. |
|
Fields to describe observed VLAN information. |
|
OS fields contain information about the operating system. |
The organization fields enrich data with information about the company or entity the data is associated with.
These fields help you arrange or filter data stored in an index by one or multiple organizations.
| Field | Description | Level |
|---|---|---|
Unique identifier for the organization. type: keyword |
extended |
|
Organization name. type: keyword Multi-fields: * organization.name.text (type: text) |
extended |
The OS fields contain information about the operating system.
| Field | Description | Level |
|---|---|---|
OS family (such as redhat, debian, freebsd, windows). type: keyword example: |
extended |
|
Operating system name, including the version or code name. type: keyword Multi-fields: * os.full.text (type: text) example: |
extended |
|
Operating system kernel version as a raw string. type: keyword example: |
extended |
|
Operating system name, without the version. type: keyword Multi-fields: * os.name.text (type: text) example: |
extended |
|
Operating system platform (such centos, ubuntu, windows). type: keyword example: |
extended |
|
Use the One of these following values should be used (lowercase): linux, macos, unix, windows. If the OS you’re dealing with is not in the list, the field should not be populated. Please let us know by opening an issue with ECS, to propose its addition. type: keyword example: |
extended |
|
Operating system version as a raw string. type: keyword example: |
extended |
The os fields are expected to be nested at: host.os, observer.os, user_agent.os.
Note also that the os fields are not expected to be used directly at the root of the events.
These fields contain information about an installed software package. It contains general information about a package, such as name, version or size. It also contains installation details, such as time or location.
| Field | Description | Level |
|---|---|---|
Package architecture. type: keyword example: |
extended |
|
Additional information about the build version of the installed package. For example use the commit SHA of a non-released package. type: keyword example: |
extended |
|
Checksum of the installed package for verification. type: keyword example: |
extended |
|
Description of the package. type: keyword example: |
extended |
|
Indicating how the package was installed, e.g. user-local, global. type: keyword example: |
extended |
|
Time when package was installed. type: date |
extended |
|
License under which the package was released. Use a short name, e.g. the license identifier from SPDX License List where possible (https://spdx.org/licenses/). type: keyword example: |
extended |
|
Package name type: keyword example: |
extended |
|
Path where the package is installed. type: keyword example: |
extended |
|
Home page or reference URL of the software in this package, if available. type: keyword example: |
extended |
|
Package size in bytes. type: long example: |
extended |
|
Type of package. This should contain the package file type, rather than the package manager name. Examples: rpm, dpkg, brew, npm, gem, nupkg, jar. type: keyword example: |
extended |
|
Package version type: keyword example: |
extended |
These fields contain Windows Portable Executable (PE) metadata.
| Field | Description | Level |
|---|---|---|
CPU architecture target for the file. type: keyword example: |
extended |
|
Internal company name of the file, provided at compile-time. type: keyword example: |
extended |
|
Internal description of the file, provided at compile-time. type: keyword example: |
extended |
|
Internal version of the file, provided at compile-time. type: keyword example: |
extended |
|
A hash of the imports in a PE file. An imphash — or import hash — can be used to fingerprint binaries even after recompilation or other code-level transformations have occurred, which would change more traditional hash values. Learn more at https://www.fireeye.com/blog/threat-research/2014/01/tracking-malware-import-hashing.html. type: keyword example: |
extended |
|
Internal name of the file, provided at compile-time. type: keyword example: |
extended |
|
Internal product name of the file, provided at compile-time. type: keyword example: |
extended |
The pe fields are expected to be nested at: dll.pe, file.pe, process.pe.
Note also that the pe fields are not expected to be used directly at the root of the events.
These fields contain information about a process.
These fields can help you correlate metrics information with a process id/name from a log message. The process.pid often stays in the metric itself and is copied to the global field for correlation.
| Field | Description | Level |
|---|---|---|
Array of process arguments, starting with the absolute path to the executable. May be filtered to protect sensitive information. type: keyword Note: this field should contain an array of values. example: |
extended |
|
Length of the process.args array. This field can be useful for querying or performing bucket analysis on how many arguments were provided to start a process. More arguments may be an indication of suspicious activity. type: long example: |
extended |
|
Full command line that started the process, including the absolute path to the executable, and all arguments. Some arguments may be filtered to protect sensitive information. type: keyword Multi-fields: * process.command_line.text (type: text) example: |
extended |
|
Unique identifier for the process. The implementation of this is specified by the data source, but some examples of what could be used here are a process-generated UUID, Sysmon Process GUIDs, or a hash of some uniquely identifying components of a process. Constructing a globally unique identifier is a common practice to mitigate PID reuse as well as to identify a specific process over time, across multiple monitored hosts. type: keyword example: |
extended |
|
Absolute path to the process executable. type: keyword Multi-fields: * process.executable.text (type: text) example: |
extended |
|
The exit code of the process, if this is a termination event. The field should be absent if there is no exit code for the event (e.g. process start). type: long example: |
extended |
|
Process name. Sometimes called program name or similar. type: keyword Multi-fields: * process.name.text (type: text) example: |
extended |
|
Identifier of the group of processes the process belongs to. type: long |
extended |
|
Process id. type: long example: |
core |
|
Parent process' pid. type: long example: |
extended |
|
The time the process started. type: date example: |
extended |
|
Thread ID. type: long example: |
extended |
|
Thread name. type: keyword example: |
extended |
|
Process title. The proctitle, some times the same as process name. Can also be different: for example a browser setting its title to the web page currently opened. type: keyword Multi-fields: * process.title.text (type: text) |
extended |
|
Seconds the process has been up. type: long example: |
extended |
|
The working directory of the process. type: keyword Multi-fields: * process.working_directory.text (type: text) example: |
extended |
The process fields are expected to be nested at: process.parent.
Note also that the process fields may be used directly at the root of the events.
| Nested fields | Description |
|---|---|
These fields contain information about binary code signatures. |
|
Hashes, usually file hashes. |
|
These fields contain information about a process. |
|
These fields contain Windows Portable Executable (PE) metadata. |
Fields related to Windows Registry operations.
| Field | Description | Level |
|---|---|---|
Original bytes written with base64 encoding. For Windows registry operations, such as SetValueEx and RegQueryValueEx, this corresponds to the data pointed by type: keyword example: |
extended |
|
Content when writing string types. Populated as an array when writing string data to the registry. For single string registry types (REG_SZ, REG_EXPAND_SZ), this should be an array with one string. For sequences of string with REG_MULTI_SZ, this array will be variable length. For numeric data, such as REG_DWORD and REG_QWORD, this should be populated with the decimal representation (e.g type: keyword Note: this field should contain an array of values. example: |
core |
|
Standard registry type for encoding contents type: keyword example: |
core |
|
Abbreviated name for the hive. type: keyword example: |
core |
|
Hive-relative path of keys. type: keyword example: |
core |
|
Full path, including hive, key and value type: keyword example: |
core |
|
Name of the value written. type: keyword example: |
core |
This field set is meant to facilitate pivoting around a piece of data.
Some pieces of information can be seen in many places in an ECS event. To facilitate searching for them, store an array of all seen values to their corresponding field in related..
A concrete example is IP addresses, which can be under host, observer, source, destination, client, server, and network.forwarded_ip. If you append all IPs to related.ip, you can then search for a given IP trivially, no matter where it appeared, by querying related.ip:192.0.2.15.
| Field | Description | Level |
|---|---|---|
All the hashes seen on your event. Populating this field, then using it to search for hashes can help in situations where you’re unsure what the hash algorithm is (and therefore which key name to search). type: keyword Note: this field should contain an array of values. |
extended |
|
All hostnames or other host identifiers seen on your event. Example identifiers include FQDNs, domain names, workstation names, or aliases. type: keyword Note: this field should contain an array of values. |
extended |
|
All of the IPs seen on your event. type: ip Note: this field should contain an array of values. |
extended |
|
All the user names seen on your event. type: keyword Note: this field should contain an array of values. |
extended |
Rule fields are used to capture the specifics of any observer or agent rules that generate alerts or other notable events.
Examples of data sources that would populate the rule fields include: network admission control platforms, network or host IDS/IPS, network firewalls, web application firewalls, url filters, endpoint detection and response (EDR) systems, etc.
| Field | Description | Level |
|---|---|---|
Name, organization, or pseudonym of the author or authors who created the rule used to generate this event. type: keyword Note: this field should contain an array of values. example: |
extended |
|
A categorization value keyword used by the entity using the rule for detection of this event. type: keyword example: |
extended |
|
The description of the rule generating the event. type: keyword example: |
extended |
|
A rule ID that is unique within the scope of an agent, observer, or other entity using the rule for detection of this event. type: keyword example: |
extended |
|
Name of the license under which the rule used to generate this event is made available. type: keyword example: |
extended |
|
The name of the rule or signature generating the event. type: keyword example: |
extended |
|
Reference URL to additional information about the rule used to generate this event. The URL can point to the vendor’s documentation about the rule. If that’s not available, it can also be a link to a more general page describing this type of alert. type: keyword |
extended |
|
Name of the ruleset, policy, group, or parent category in which the rule used to generate this event is a member. type: keyword example: |
extended |
|
A rule ID that is unique within the scope of a set or group of agents, observers, or other entities using the rule for detection of this event. type: keyword example: |
extended |
|
The version / revision of the rule being used for analysis. type: keyword example: |
extended |
A Server is defined as the responder in a network connection for events regarding sessions, connections, or bidirectional flow records.
For TCP events, the server is the receiver of the initial SYN packet(s) of the TCP connection. For other protocols, the server is generally the responder in the network transaction. Some systems actually use the term "responder" to refer the server in TCP connections. The server fields describe details about the system acting as the server in the network event. Server fields are usually populated in conjunction with client fields. Server fields are generally not populated for packet-level events.
Client / server representations can add semantic context to an exchange, which is helpful to visualize the data in certain situations. If your context falls in that category, you should still ensure that source and destination are filled appropriately.
| Field | Description | Level |
|---|---|---|
Some event server addresses are defined ambiguously. The event will sometimes list an IP, a domain or a unix socket. You should always store the raw address in the Then it should be duplicated to type: keyword |
extended |
|
Bytes sent from the server to the client. type: long example: |
core |
|
Server domain. type: keyword |
core |
|
IP address of the server (IPv4 or IPv6). type: ip |
core |
|
MAC address of the server. The notation format from RFC 7042 is suggested: Each octet (that is, 8-bit byte) is represented by two [uppercase] hexadecimal digits giving the value of the octet as an unsigned integer. Successive octets are separated by a hyphen. type: keyword example: |
core |
|
Translated ip of destination based NAT sessions (e.g. internet to private DMZ) Typically used with load balancers, firewalls, or routers. type: ip |
extended |
|
Translated port of destination based NAT sessions (e.g. internet to private DMZ) Typically used with load balancers, firewalls, or routers. type: long |
extended |
|
Packets sent from the server to the client. type: long example: |
core |
|
Port of the server. type: long |
core |
|
The highest registered server domain, stripped of the subdomain. For example, the registered domain for "foo.example.com" is "example.com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last two labels will not work well for TLDs such as "co.uk". type: keyword example: |
extended |
|
The subdomain portion of a fully qualified domain name includes all of the names except the host name under the registered_domain. In a partially qualified domain, or if the the qualification level of the full name cannot be determined, subdomain contains all of the names below the registered domain. For example the subdomain portion of "www.east.mydomain.co.uk" is "east". If the domain has multiple levels of subdomain, such as "sub2.sub1.example.com", the subdomain field should contain "sub2.sub1", with no trailing period. type: keyword example: |
extended |
|
The effective top level domain (eTLD), also known as the domain suffix, is the last part of the domain name. For example, the top level domain for example.com is "com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last label will not work well for effective TLDs such as "co.uk". type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
Fields describing an Autonomous System (Internet routing prefix). |
|
Fields describing a location. |
|
Fields to describe the user relevant to the event. |
The service fields describe the service for or from which the data was collected.
These fields help you find and correlate logs for a specific service and version.
| Field | Description | Level |
|---|---|---|
Ephemeral identifier of this service (if one exists). This id normally changes across restarts, but type: keyword example: |
extended |
|
Unique identifier of the running service. If the service is comprised of many nodes, the This id should uniquely identify the service. This makes it possible to correlate logs and metrics for one specific service, no matter which particular node emitted the event. Note that if you need to see the events from one specific host of the service, you should filter on that type: keyword example: |
core |
|
Name of the service data is collected from. The name of the service is normally user given. This allows for distributed services that run on multiple hosts to correlate the related instances based on the name. In the case of Elasticsearch the type: keyword example: |
core |
|
Name of a service node. This allows for two nodes of the same service running on the same host to be differentiated. Therefore, In the case of Elasticsearch, the type: keyword example: |
extended |
|
Current state of the service. type: keyword |
core |
|
The type of the service data is collected from. The type can be used to group and correlate logs and metrics from one service type. Example: If logs or metrics are collected from Elasticsearch, type: keyword example: |
core |
|
Version of the service the data was collected from. This allows to look at a data set only for a specific version of a service. type: keyword example: |
core |
Source fields capture details about the sender of a network exchange/packet. These fields are populated from a network event, packet, or other event containing details of a network transaction.
Source fields are usually populated in conjunction with destination fields. The source and destination fields are considered the baseline and should always be filled if an event contains source and destination details from a network transaction. If the event also contains identification of the client and server roles, then the client and server fields should also be populated.
| Field | Description | Level |
|---|---|---|
Some event source addresses are defined ambiguously. The event will sometimes list an IP, a domain or a unix socket. You should always store the raw address in the Then it should be duplicated to type: keyword |
extended |
|
Bytes sent from the source to the destination. type: long example: |
core |
|
Source domain. type: keyword |
core |
|
IP address of the source (IPv4 or IPv6). type: ip |
core |
|
MAC address of the source. The notation format from RFC 7042 is suggested: Each octet (that is, 8-bit byte) is represented by two [uppercase] hexadecimal digits giving the value of the octet as an unsigned integer. Successive octets are separated by a hyphen. type: keyword example: |
core |
|
Translated ip of source based NAT sessions (e.g. internal client to internet) Typically connections traversing load balancers, firewalls, or routers. type: ip |
extended |
|
Translated port of source based NAT sessions. (e.g. internal client to internet) Typically used with load balancers, firewalls, or routers. type: long |
extended |
|
Packets sent from the source to the destination. type: long example: |
core |
|
Port of the source. type: long |
core |
|
The highest registered source domain, stripped of the subdomain. For example, the registered domain for "foo.example.com" is "example.com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last two labels will not work well for TLDs such as "co.uk". type: keyword example: |
extended |
|
The subdomain portion of a fully qualified domain name includes all of the names except the host name under the registered_domain. In a partially qualified domain, or if the the qualification level of the full name cannot be determined, subdomain contains all of the names below the registered domain. For example the subdomain portion of "www.east.mydomain.co.uk" is "east". If the domain has multiple levels of subdomain, such as "sub2.sub1.example.com", the subdomain field should contain "sub2.sub1", with no trailing period. type: keyword example: |
extended |
|
The effective top level domain (eTLD), also known as the domain suffix, is the last part of the domain name. For example, the top level domain for example.com is "com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last label will not work well for effective TLDs such as "co.uk". type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
Fields describing an Autonomous System (Internet routing prefix). |
|
Fields describing a location. |
|
Fields to describe the user relevant to the event. |
Fields to classify events and alerts according to a threat taxonomy such as the MITRE ATT&CK® framework.
These fields are for users to classify alerts from all of their sources (e.g. IDS, NGFW, etc.) within a common taxonomy. The threat.tactic.* are meant to capture the high level category of the threat (e.g. "impact"). The threat.technique.* fields are meant to capture which kind of approach is used by this detected threat, to accomplish the goal (e.g. "endpoint denial of service").
| Field | Description | Level |
|---|---|---|
Name of the threat framework used to further categorize and classify the tactic and technique of the reported threat. Framework classification can be provided by detecting systems, evaluated at ingest time, or retrospectively tagged to events. type: keyword example: |
extended |
|
The id of tactic used by this threat. You can use a MITRE ATT&CK® tactic, for example. (ex. https://attack.mitre.org/tactics/TA0002/ ) type: keyword Note: this field should contain an array of values. example: |
extended |
|
Name of the type of tactic used by this threat. You can use a MITRE ATT&CK® tactic, for example. (ex. https://attack.mitre.org/tactics/TA0002/) type: keyword Note: this field should contain an array of values. example: |
extended |
|
The reference url of tactic used by this threat. You can use a MITRE ATT&CK® tactic, for example. (ex. https://attack.mitre.org/tactics/TA0002/ ) type: keyword Note: this field should contain an array of values. |
extended |
|
The id of technique used by this threat. You can use a MITRE ATT&CK® technique, for example. (ex. https://attack.mitre.org/techniques/T1059/) type: keyword Note: this field should contain an array of values. example: |
extended |
|
The name of technique used by this threat. You can use a MITRE ATT&CK® technique, for example. (ex. https://attack.mitre.org/techniques/T1059/) type: keyword Multi-fields: * threat.technique.name.text (type: text) Note: this field should contain an array of values. example: |
extended |
|
The reference url of technique used by this threat. You can use a MITRE ATT&CK® technique, for example. (ex. https://attack.mitre.org/techniques/T1059/) type: keyword Note: this field should contain an array of values. |
extended |
|
The full id of subtechnique used by this threat. You can use a MITRE ATT&CK® subtechnique, for example. (ex. https://attack.mitre.org/techniques/T1059/001/) type: keyword Note: this field should contain an array of values. example: |
extended |
|
The name of subtechnique used by this threat. You can use a MITRE ATT&CK® subtechnique, for example. (ex. https://attack.mitre.org/techniques/T1059/001/) type: keyword Multi-fields: * threat.technique.subtechnique.name.text (type: text) Note: this field should contain an array of values. example: |
extended |
|
The reference url of subtechnique used by this threat. You can use a MITRE ATT&CK® subtechnique, for example. (ex. https://attack.mitre.org/techniques/T1059/001/) type: keyword Note: this field should contain an array of values. |
extended |
Fields related to a TLS connection. These fields focus on the TLS protocol itself and intentionally avoids in-depth analysis of the related x.509 certificate files.
| Field | Description | Level |
|---|---|---|
String indicating the cipher used during the current connection. type: keyword example: |
extended |
|
PEM-encoded stand-alone certificate offered by the client. This is usually mutually-exclusive of type: keyword example: |
extended |
|
Array of PEM-encoded certificates that make up the certificate chain offered by the client. This is usually mutually-exclusive of type: keyword Note: this field should contain an array of values. example: |
extended |
|
Certificate fingerprint using the MD5 digest of DER-encoded version of certificate offered by the client. For consistency with other hash values, this value should be formatted as an uppercase hash. type: keyword example: |
extended |
|
Certificate fingerprint using the SHA1 digest of DER-encoded version of certificate offered by the client. For consistency with other hash values, this value should be formatted as an uppercase hash. type: keyword example: |
extended |
|
Certificate fingerprint using the SHA256 digest of DER-encoded version of certificate offered by the client. For consistency with other hash values, this value should be formatted as an uppercase hash. type: keyword example: |
extended |
|
Distinguished name of subject of the issuer of the x.509 certificate presented by the client. type: keyword example: |
extended |
|
A hash that identifies clients based on how they perform an SSL/TLS handshake. type: keyword example: |
extended |
|
Date/Time indicating when client certificate is no longer considered valid. type: date example: |
extended |
|
Date/Time indicating when client certificate is first considered valid. type: date example: |
extended |
|
Also called an SNI, this tells the server which hostname to which the client is attempting to connect to. When this value is available, it should get copied to type: keyword example: |
extended |
|
Distinguished name of subject of the x.509 certificate presented by the client. type: keyword example: |
extended |
|
Array of ciphers offered by the client during the client hello. type: keyword Note: this field should contain an array of values. example: |
extended |
|
String indicating the curve used for the given cipher, when applicable. type: keyword example: |
extended |
|
Boolean flag indicating if the TLS negotiation was successful and transitioned to an encrypted tunnel. type: boolean |
extended |
|
String indicating the protocol being tunneled. Per the values in the IANA registry (https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml#alpn-protocol-ids), this string should be lower case. type: keyword example: |
extended |
|
Boolean flag indicating if this TLS connection was resumed from an existing TLS negotiation. type: boolean |
extended |
|
PEM-encoded stand-alone certificate offered by the server. This is usually mutually-exclusive of type: keyword example: |
extended |
|
Array of PEM-encoded certificates that make up the certificate chain offered by the server. This is usually mutually-exclusive of type: keyword Note: this field should contain an array of values. example: |
extended |
|
Certificate fingerprint using the MD5 digest of DER-encoded version of certificate offered by the server. For consistency with other hash values, this value should be formatted as an uppercase hash. type: keyword example: |
extended |
|
Certificate fingerprint using the SHA1 digest of DER-encoded version of certificate offered by the server. For consistency with other hash values, this value should be formatted as an uppercase hash. type: keyword example: |
extended |
|
Certificate fingerprint using the SHA256 digest of DER-encoded version of certificate offered by the server. For consistency with other hash values, this value should be formatted as an uppercase hash. type: keyword example: |
extended |
|
Subject of the issuer of the x.509 certificate presented by the server. type: keyword example: |
extended |
|
A hash that identifies servers based on how they perform an SSL/TLS handshake. type: keyword example: |
extended |
|
Timestamp indicating when server certificate is no longer considered valid. type: date example: |
extended |
|
Timestamp indicating when server certificate is first considered valid. type: date example: |
extended |
|
Subject of the x.509 certificate presented by the server. type: keyword example: |
extended |
|
Numeric part of the version parsed from the original string. type: keyword example: |
extended |
|
Normalized lowercase protocol name parsed from original string. type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
These fields contain x509 certificate metadata. |
|
These fields contain x509 certificate metadata. |
Distributed tracing makes it possible to analyze performance throughout a microservice architecture all in one view. This is accomplished by tracing all of the requests - from the initial web request in the front-end service - to queries made through multiple back-end services.
Unlike most field sets in ECS, the tracing fields are not nested under the field set name. In other words, the correct field name is trace.id, not tracing.trace.id, and so on.
| Field | Description | Level |
|---|---|---|
Unique identifier of the span within the scope of its trace. A span represents an operation within a transaction, such as a request to another service, or a database query. type: keyword example: |
extended |
|
Unique identifier of the trace. A trace groups multiple events like transactions that belong together. For example, a user request handled by multiple inter-connected services. type: keyword example: |
extended |
|
Unique identifier of the transaction within the scope of its trace. A transaction is the highest level of work measured within a service, such as a request to a server. type: keyword example: |
extended |
URL fields provide support for complete or partial URLs, and supports the breaking down into scheme, domain, path, and so on.
| Field | Description | Level |
|---|---|---|
Domain of the url, such as "www.elastic.co". In some cases a URL may refer to an IP and/or port directly, without a domain name. In this case, the IP address would go to the If the URL contains a literal IPv6 address enclosed by type: keyword example: |
extended |
|
The field contains the file extension from the original request url, excluding the leading dot. The file extension is only set if it exists, as not every url has a file extension. The leading period must not be included. For example, the value must be "png", not ".png". Note that when the file name has multiple extensions (example.tar.gz), only the last one should be captured ("gz", not "tar.gz"). type: keyword example: |
extended |
|
Portion of the url after the The type: keyword |
extended |
|
If full URLs are important to your use case, they should be stored in type: keyword Multi-fields: * url.full.text (type: text) example: |
extended |
|
Unmodified original url as seen in the event source. Note that in network monitoring, the observed URL may be a full URL, whereas in access logs, the URL is often just represented as a path. This field is meant to represent the URL as it was observed, complete or not. type: keyword Multi-fields: * url.original.text (type: text) example: |
extended |
|
Password of the request. type: keyword |
extended |
|
Path of the request, such as "/search". type: keyword |
extended |
|
Port of the request, such as 443. type: long example: |
extended |
|
The query field describes the query string of the request, such as "q=elasticsearch". The type: keyword |
extended |
|
The highest registered url domain, stripped of the subdomain. For example, the registered domain for "foo.example.com" is "example.com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last two labels will not work well for TLDs such as "co.uk". type: keyword example: |
extended |
|
Scheme of the request, such as "https". Note: The type: keyword example: |
extended |
|
The subdomain portion of a fully qualified domain name includes all of the names except the host name under the registered_domain. In a partially qualified domain, or if the the qualification level of the full name cannot be determined, subdomain contains all of the names below the registered domain. For example the subdomain portion of "www.east.mydomain.co.uk" is "east". If the domain has multiple levels of subdomain, such as "sub2.sub1.example.com", the subdomain field should contain "sub2.sub1", with no trailing period. type: keyword example: |
extended |
|
The effective top level domain (eTLD), also known as the domain suffix, is the last part of the domain name. For example, the top level domain for example.com is "com". This value can be determined precisely with a list like the public suffix list (http://publicsuffix.org). Trying to approximate this by simply taking the last label will not work well for effective TLDs such as "co.uk". type: keyword example: |
extended |
|
Username of the request. type: keyword |
extended |
The user fields describe information about the user that is relevant to the event.
Fields can have one entry or multiple entries. If a user has more than one id, provide an array that includes all of them.
Find additional usage and examples in the user fields usage section.
| Field | Description | Level |
|---|---|---|
Name of the directory the user is a member of. For example, an LDAP or Active Directory domain name. type: keyword |
extended |
|
User email address. type: keyword |
extended |
|
User’s full name, if available. type: keyword Multi-fields: * user.full_name.text (type: text) example: |
extended |
|
Unique user hash to correlate information for a user in anonymized form. Useful if type: keyword |
extended |
|
Unique identifier of the user. type: keyword |
core |
|
Short name or login of the user. type: keyword Multi-fields: * user.name.text (type: text) example: |
core |
|
Array of user roles at the time of the event. type: keyword Note: this field should contain an array of values. example: |
extended |
The user fields are expected to be nested at: client.user, destination.user, host.user, server.user, source.user, user.changes, user.effective, user.target.
Note also that the user fields may be used directly at the root of the events.
| Nested fields | Description |
|---|---|
Fields to describe the user relevant to the event. |
|
Fields to describe the user relevant to the event. |
|
User’s group relevant to the event. |
|
Fields to describe the user relevant to the event. |
The user_agent fields normally come from a browser request.
They often show up in web service logs coming from the parsed user agent string.
| Field | Description | Level |
|---|---|---|
Name of the device. type: keyword example: |
extended |
|
Name of the user agent. type: keyword example: |
extended |
|
Unparsed user_agent string. type: keyword Multi-fields: * user_agent.original.text (type: text) example: |
extended |
|
Version of the user agent. type: keyword example: |
extended |
| Nested fields | Description |
|---|---|
OS fields contain information about the operating system. |
The VLAN fields are used to identify 802.1q tag(s) of a packet, as well as ingress and egress VLAN associations of an observer in relation to a specific packet or connection.
Network.vlan fields are used to record a single VLAN tag, or the outer tag in the case of q-in-q encapsulations, for a packet or connection as observed, typically provided by a network sensor (e.g. Zeek, Wireshark) passively reporting on traffic.
Network.inner VLAN fields are used to report inner q-in-q 802.1q tags (multiple 802.1q encapsulations) as observed, typically provided by a network sensor (e.g. Zeek, Wireshark) passively reporting on traffic. Network.inner VLAN fields should only be used in addition to network.vlan fields to indicate q-in-q tagging.
Observer.ingress and observer.egress VLAN values are used to record observer specific information when observer events contain discrete ingress and egress VLAN information, typically provided by firewalls, routers, or load balancers.
| Field | Description | Level |
|---|---|---|
VLAN ID as reported by the observer. type: keyword example: |
extended |
|
Optional VLAN name as reported by the observer. type: keyword example: |
extended |
The vlan fields are expected to be nested at: network.inner.vlan, network.vlan, observer.egress.vlan, observer.ingress.vlan.
Note also that the vlan fields are not expected to be used directly at the root of the events.
The vulnerability fields describe information about a vulnerability that is relevant to an event.
| Field | Description | Level |
|---|---|---|
The type of system or architecture that the vulnerability affects. These may be platform-specific (for example, Debian or SUSE) or general (for example, Database or Firewall). For example (Qualys vulnerability categories) This field must be an array. type: keyword Note: this field should contain an array of values. example: |
extended |
|
The classification of the vulnerability scoring system. For example (https://www.first.org/cvss/) type: keyword example: |
extended |
|
The description of the vulnerability that provides additional context of the vulnerability. For example (Common Vulnerabilities and Exposure CVE description) type: keyword Multi-fields: * vulnerability.description.text (type: text) example: |
extended |
|
The type of identifier used for this vulnerability. For example (https://cve.mitre.org/about/) type: keyword example: |
extended |
|
The identification (ID) is the number portion of a vulnerability entry. It includes a unique identification number for the vulnerability. For example (Common Vulnerabilities and Exposure CVE ID type: keyword example: |
extended |
|
A resource that provides additional information, context, and mitigations for the identified vulnerability. type: keyword example: |
extended |
|
The report or scan identification number. type: keyword example: |
extended |
|
The name of the vulnerability scanner vendor. type: keyword example: |
extended |
|
Scores can range from 0.0 to 10.0, with 10.0 being the most severe. Base scores cover an assessment for exploitability metrics (attack vector, complexity, privileges, and user interaction), impact metrics (confidentiality, integrity, and availability), and scope. For example (https://www.first.org/cvss/specification-document) type: float example: |
extended |
|
Scores can range from 0.0 to 10.0, with 10.0 being the most severe. Environmental scores cover an assessment for any modified Base metrics, confidentiality, integrity, and availability requirements. For example (https://www.first.org/cvss/specification-document) type: float example: |
extended |
|
Scores can range from 0.0 to 10.0, with 10.0 being the most severe. Temporal scores cover an assessment for code maturity, remediation level, and confidence. For example (https://www.first.org/cvss/specification-document) type: float |
extended |
|
The National Vulnerability Database (NVD) provides qualitative severity rankings of "Low", "Medium", and "High" for CVSS v2.0 base score ranges in addition to the severity ratings for CVSS v3.0 as they are defined in the CVSS v3.0 specification. CVSS is owned and managed by FIRST.Org, Inc. (FIRST), a US-based non-profit organization, whose mission is to help computer security incident response teams across the world. For example (https://nvd.nist.gov/vuln-metrics/cvss) type: keyword example: |
extended |
|
The severity of the vulnerability can help with metrics and internal prioritization regarding remediation. For example (https://nvd.nist.gov/vuln-metrics/cvss) type: keyword example: |
extended |
This implements the common core fields for x509 certificates. This information is likely logged with TLS sessions, digital signatures found in executable binaries, S/MIME information in email bodies, or analysis of files on disk.
When the certificate relates to a file, use the fields at file.x509. When hashes of the DER-encoded certificate are available, the hash data set should be populated as well (e.g. file.hash.sha256).
Events that contain certificate information about network connections, should use the x509 fields under the relevant TLS fields: tls.server.x509 and/or tls.client.x509.
| Field | Description | Level |
|---|---|---|
List of subject alternative names (SAN). Name types vary by certificate authority and certificate type but commonly contain IP addresses, DNS names (and wildcards), and email addresses. type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of common name (CN) of issuing certificate authority. type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of country © codes type: keyword Note: this field should contain an array of values. example: |
extended |
|
Distinguished name (DN) of issuing certificate authority. type: keyword example: |
extended |
|
List of locality names (L) type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of organizations (O) of issuing certificate authority. type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of organizational units (OU) of issuing certificate authority. type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of state or province names (ST, S, or P) type: keyword Note: this field should contain an array of values. example: |
extended |
|
Time at which the certificate is no longer considered valid. type: date example: |
extended |
|
Time at which the certificate is first considered valid. type: date example: |
extended |
|
Algorithm used to generate the public key. type: keyword example: |
extended |
|
The curve used by the elliptic curve public key algorithm. This is algorithm specific. type: keyword example: |
extended |
|
Exponent used to derive the public key. This is algorithm specific. type: long example: |
extended |
|
The size of the public key space in bits. type: long example: |
extended |
|
Unique serial number issued by the certificate authority. For consistency, if this value is alphanumeric, it should be formatted without colons and uppercase characters. type: keyword example: |
extended |
|
Identifier for certificate signature algorithm. We recommend using names found in Go Lang Crypto library. See https://github.com/golang/go/blob/go1.14/src/crypto/x509/x509.go#L337-L353. type: keyword example: |
extended |
|
List of common names (CN) of subject. type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of country © code type: keyword Note: this field should contain an array of values. example: |
extended |
|
Distinguished name (DN) of the certificate subject entity. type: keyword example: |
extended |
|
List of locality names (L) type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of organizations (O) of subject. type: keyword Note: this field should contain an array of values. example: |
extended |
|
List of organizational units (OU) of subject. type: keyword Note: this field should contain an array of values. |
extended |
|
List of state or province names (ST, S, or P) type: keyword Note: this field should contain an array of values. example: |
extended |
|
Version of x509 format. type: keyword example: |
extended |
The x509 fields are expected to be nested at: file.x509, tls.client.x509, tls.server.x509.
Note also that the x509 fields are not expected to be used directly at the root of the events.