Name:Linux Shell History Access Via Command Line Utility id:0e4c2544-b27a-4a2d-b9be-cac8efe515fb version:1 date:None author:Raven Tait, Splunk status:production type:Anomaly Description:The following analytic detects attempts to read shell history files (bash, zsh, fish, etc.).
A history file is a log file that records all the commands executed in a shell on a Linux or Unix-based operating system.
A malicious actor who gains access to a user's shell history file can potentially obtain sensitive information and use it to compromise the user's system and data. Data_source:
-Sysmon for Linux EventID 1
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime
how_to_implement:The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process. known_false_positives:Legitimate system administrators and automated scripts may access shell history files for auditing or troubleshooting purposes. Filter based on known administrative accounts and approved tooling in your environment. References: drilldown_searches: earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View the detection results for - "$user$" and "$dest$"' search:'%original_detection_search% | search user = "$user$" dest = "$dest$"' name:'View risk events for the last 7 days for - "$user$" and "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | 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:'7d' latest_offset:'0' analytic_story:['Linux Post-Exploitation', 'Compromised Linux Host', 'Linux Privilege Escalation', 'Linux Persistence Techniques', 'Credential Dumping']
