Linux AWK Privilege Escalation

name: Linux AWK Privilege Escalation
id: 4510cae0-96a2-4840-9919-91d262db210a
version: 11
date: '2026-03-10'
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.action Processes.dest Processes.original_file_name
         Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
         Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
         Processes.process Processes.process_exec Processes.process_guid
         Processes.process_hash Processes.process_id Processes.process_integrity_level
         Processes.process_name Processes.process_path Processes.user
         Processes.user_id Processes.vendor_product
    | `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: $info_max_time$
rba:
    message: An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$
    risk_objects:
        - field: dest
          type: system
          score: 20
    threat_objects:
        - field: parent_process_name
          type: parent_process_name
        - field: process_name
          type: process_name
tags:
    analytic_story:
        - Linux Privilege Escalation
        - Linux Living Off The Land
    asset_type: Endpoint
    mitre_attack_id:
        - T1548.003
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548/awk/sysmon_linux.log
          source: Syslog:Linux-Sysmon/Operational
          sourcetype: sysmon:linux