Name:Linux Service Restarted id:084275ba-61b8-11ec-8d64-acde48001122 version:3 date:2024-09-30 author:Teoderick Contreras, Splunk status:production type:Anomaly Description:The following analytic detects the restarting or re-enabling of services on Linux systems using the `systemctl` or `service` commands. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and command-line execution logs. This activity is significant as adversaries may use it to maintain persistence or execute unauthorized actions. If confirmed malicious, this behavior could lead to repeated execution of malicious payloads, unauthorized access, or data destruction. Security analysts should investigate these events to mitigate risks and prevent further compromise. Data_source:
-Sysmon for Linux EventID 1
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name IN ("systemctl", "service") OR Processes.process IN ("*systemctl *", "*service *")) Processes.process IN ("*restart*", "*reload*", "*reenable*") by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id Processes.process_guid | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `linux_service_restarted_filter`
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:Administrator or network operator can use this commandline for automation purposes. Please update the filter macros to remove false positives. References: -https://attack.mitre.org/techniques/T1543/003/ 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: - 'AwfulShred' - 'Linux Privilege Escalation' - 'Linux Living Off The Land' - 'Data Destruction' - 'Linux Persistence Techniques' - 'Scheduled Tasks' - 'Gomir' asset_type:Endpoint confidence:50 impact:50 message:A commandline $process$ that may create or start a service on $dest$ mitre_attack_id: - 'T1053.006' - 'T1053' observable: name:'dest' type:'Hostname' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'Processes.dest' - 'Processes.user' - 'Processes.parent_process_name' - 'Processes.process_name' - 'Processes.process' - 'Processes.process_id' - 'Processes.parent_process_id' risk_score:25 security_domain:endpoint
