Splunk Tools

Collection of Splunking Tools, SPL Code and Resources

Table of Contents

• SPL Examples
• Splunk Hunting and IOCs
• Sysmon Monitoring
• Threat Intelligence Applications
• Document Resources
• Online Resources

SPL Examples

Find Windows Security Event Code Info

index=win_servers sourcetype=windows:security
| table EventCode

Find New Local Admin Accounts

 index=win_servers sourcetype=windows:security EventCode=4720 OR (EventCode=4732 Administrators)
 | transaction Security_ID maxspan=180m
 | search EventCode=4720 EventCode=4732
 | table _time, EventCode, Security_ID, SamAccountName

Note:

• 4720: new user created
• 4732: user added to security group
• 4624: successful user login

Detect Network and Port Scanning

index=* sourcetype=firewall*
| stats dc(dest_port) as num_dest_port dc(dest_ip) as num_dest_ip by src_ip
| where num_dest_port >500 OR num_dest_ip > 500

Note: internal scanning > external scanning

Find Interactive Logins from Service Accounts

index=systems sourcetype=audit_logs user=svc_*
| table _time dest user

Find Outlier Interactive Logins

index=systems sourcetype=audit_logs user=svc_*
| stats earliest(_time) as earliest latest(_time) as latest by user, dest
| eval isOutlier=if(earliest >= relative_time(now(), "-1d@d"), 1, 0)
| convert ctime(earliest) ctime(latest)
| where isOutlier=1 

Detect Bruce Force Attacks

index=* sourcetype=win*security user=* user!=""
| stats count(eval(action="success")) as successes count(eval(action="failure")) as failures by user, ComputerName
| where successes>0 AND failures>100

Basic TOR Detection

index=network sourcetype=firewall_data app=tor src_ip=*
| table _time src_ip src_port dest_ip dest_port bytes app

Detect Recurring Malware on Host

index=* sourcetype=symantec:* 
| stats count range(_time) as TimeRange by Risk_Name, Computer_Name
| where TimeRange>1800
| eval TimeRange_In_Hours = round(TimeRange/3600,2), TimeRange_In_Days = round (TimeRange/3600/24,2)

Detect Windows Audit Log Tampering

index=* (sourcetype=wineventlog AND (EventCode=1102 OR EventCode=1100)) OR (sourcetype=wineventlog AND EventCode=104)
| stats count by _time EventCode Message sourcetype host

Note:

• 1102: security log cleared
• 1100: event logging service shutdown
• 104: event log cleared

Find Large Web Uploads

index=* sourcetype=websense* 
| where bytes_out > 35000000
| table _time src_ip bytes* uri

List Web Users by Country

index=web sourcetype=access_combined
| iplocation clientip
| stats dc(clientip) by Country

List Web Users by Country on Map

index=web sourcetype=access_combined
| iplocation clientip
| geostats dc(clientip) by Country

Detect Unencrypted Web Communications

index=* sourcetype=firewall_data dest_port!=443 app=workday*
| table _time user app bytes* src_ip dest_ip dest_port

Show Log Volume Trending

| tstats prestats=t count WHERE index=apps by host _time span=1m
| timechart partial=f span=1m count by host limit=0

Measure Memory Utilization by Host Chart

index=main sourcetype=vmstat
| timechart max(memUsedPct) by host

Show Hosts with High Memory Utilization

index=main sourcetype=vmstat
| stats max(memUsedPct) as memused by host
| where memused>80

Splunk Hunting and IOCs

Search for changes related to the following items/IOCs during threat-hunting/incident response:

• Applications Using Wrong Ports
• Coin Address
• DNS Anomolies
• Domain Names
• Email Addresses
• Email Subject Lines
• File Names
• File Path
• Geolocation
• Hashes
• HTML Response Sizes
• Increased network usage
• IP Addresses
• MAC Addresses
• Mutex Names
• Passwords
• Registry Keys
• Registry Values
• Service Name
• Strings
• TLS Certificate Serial Numbers
• Unusual privileged account activity
• URL
• Usernames

Sysmon Monitoring

Install Sysinternals Sysmon Service Driver, Use MD4, Log Modules & Network Connections:

sysmon.exe -i -h md5 -l -n

SysInternals

• Live Sysinternals

Sysmon Configuration File Template

• sysmonconfig-export.xml
• SwiftOnSecurity Sysmon Configuration File

Threat Intelligence Applications

• Splunk ThreatHunting App
  • ThreatHunting Resources
  • ThreatHunting Guide
• Splunk Enterprise Security
  • Splunk Enterprise Security Guide
  • Detect Sunburst Backdoor using Splunk Enterprise Security
• Splunk Security Essentials
• Dragos Threat Intelligence

Document Resources

• Splunk Quick Reference Guide
• Splunk Search Cheat Sheet
• Operationalizing Threat Intelligence Using Splunk Enterprise Security
• Splunk IOCs: Indicators of Crap Presentation
• Windows LOG-MD ATT&CK Cheat Sheet
• Windows ATT&CK Logging Cheat Sheet
• Windows Logging Cheat Sheet
• Windows Advanced Logging Cheat Sheet
• Windows File Auditing Cheat Sheet
• Windows PowerShell Logging Cheat Sheet
• Windows Registry Auditing Cheat Sheet
• Windows Splunk Logging Cheat Sheet
• Windows Sysmon Logging Cheat Sheet

Online Resources

• RegEx 101
• Mockaroo fake data generator
• Crontab Guru for Cron Expressions
• whois
• Windows Event Logs Defined
• Windows Security Log Events
• Windows Logging Cheat Sheets
• MITRE ATT&CK
• MITRE File Scanning
• ARTHIR
• Splunk Lookups for IOCs
• Accelerating Forensic Triage with Splunk
• Splunk for IR and Forensics 1
  • Splunk for IR and Forensics 2
• Windows Log Malicious Discover Log-MD