non_chrome_process_accessing_chrome_default_dir.yml

name: Non Chrome Process Accessing Chrome Default Dir
id: 81263de4-160a-11ec-944f-acde48001122
version: 3
date: '2024-05-25'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: The following analytic detects a non-Chrome process accessing files in
  the Chrome user default folder. It leverages Windows Security Event logs, specifically
  event code 4663, to identify unauthorized access attempts. This activity is significant
  because the Chrome default folder contains sensitive user data such as login credentials,
  browsing history, and cookies. If confirmed malicious, this behavior could indicate
  an attempt to exfiltrate sensitive information, often associated with RATs, trojans,
  and advanced persistent threats like FIN7. Such access could lead to data theft
  and further compromise of the affected system.
data_source:
- Windows Event Log Security 4663
search: '`wineventlog_security` EventCode=4663 NOT (ProcessName IN ("*\\chrome.exe",
  "*\\explorer.exe", "*sql*")) ObjectName="*\\Google\\Chrome\\User Data\\Default*"
  | stats count min(_time) as firstTime max(_time) as lastTime by ObjectName ObjectType
  ProcessName AccessMask EventCode dest | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
  | `non_chrome_process_accessing_chrome_default_dir_filter`'
how_to_implement: To successfully implement this search, you must ingest Windows Security
  Event logs and track event code 4663. For 4663, enable "Audit Object Access" in
  Group Policy. Then check the two boxes listed for both "Success" and "Failure."
known_false_positives: other browser not listed related to chrome may catch by this
  rule.
references: []
tags:
  analytic_story:
  - Remcos
  - NjRAT
  - Warzone RAT
  - 3CX Supply Chain Attack
  - RedLine Stealer
  - FIN7
  - DarkGate Malware
  - AgentTesla
  - CISA AA23-347A
  - Phemedrone Stealer
  - Snake Keylogger
  asset_type: Endpoint
  confidence: 70
  impact: 50
  message: a non chrome browser process $ProcessName$ accessing $ObjectName$
  mitre_attack_id:
  - T1555
  - T1555.003
  observable:
  - name: dest
    type: Endpoint
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Object_Name
  - Object_Type
  - process_name
  - Access_Mask
  - Accesses
  - process_id
  - EventCode
  - dest
  - user
  risk_score: 35
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: 
      https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1555/non_chrome_process_accessing_chrome_default_dir/windows-xml.log
    source: XmlWinEventLog:Security
    sourcetype: XmlWinEventLog