Name:Non Chrome Process Accessing Chrome Default Dir id:81263de4-160a-11ec-944f-acde48001122 version:4 date:2024-09-30 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: drilldown_searches: name:'View the detection results for - "$dest$"' search:'%original_detection_search% | search dest = "$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' 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
