Name:Linux AWK Privilege Escalation id:4510cae0-96a2-4840-9919-91d262db210a version:4 date:2024-09-30 author:Gowthamaraj Rajendran, Splunk status:production type:Anomaly Description:The following analytic detects the use of the AWK command with elevated privileges to execute system commands. It leverages Endpoint Detection and Response (EDR) telemetry, specifically monitoring processes that include "sudo," "awk," and "BEGIN*system" in their command lines. This activity is significant because it indicates a potential privilege escalation attempt, where a user could gain root access by executing commands as the root user. If confirmed malicious, this could allow an attacker to fully compromise the system, execute arbitrary commands, and maintain persistent control over the affected endpoint. 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="*sudo*" AND Processes.process="*awk*" AND Processes.process="*BEGIN*system*" 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_awk_privilege_escalation_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:False positives are present based on automated tooling or system administrative usage. Filter as needed. References: -https://www.hacknos.com/awk-privilege-escalation/ 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: - 'Linux Privilege Escalation' - 'Linux Living Off The Land' asset_type:Endpoint confidence:50 impact:60 message:An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ mitre_attack_id: - 'T1548.003' - 'T1548' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'parent_process_name' type:'Process' - role: - 'Attacker' name:'process_name' type:'Process' - role: - 'Attacker' 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:30 security_domain:endpoint
