Linux Common Process For Elevation Control

Name:Linux Common Process For Elevation Control
id:66ab15c0-63d0-11ec-9e70-acde48001122
version:8
date:2025-03-27
author:Teoderick Contreras, Splunk
status:production
type:Hunting
Description:The following analytic identifies the execution of common Linux processes used for elevation control, such as `chmod`, `chown`, and `setuid`. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant because these processes are often abused by adversaries to gain persistence or escalate privileges on compromised hosts. If confirmed malicious, this behavior could allow attackers to modify file attributes, change file ownership, or set user IDs, potentially leading to unauthorized access and control over critical system resources.
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 ("chmod", "chown", "fchmod", "fchmodat", "fchown", "fchownat", "fremovexattr", "fsetxattr", "lchown", "lremovexattr", "lsetxattr", "removexattr", "setuid", "setgid", "setreuid", "setregid", "chattr") OR Processes.process IN ("*chmod *", "*chown *", "*fchmod *", "*fchmodat *", "*fchown *", "*fchownat *", "*fremovexattr *", "*fsetxattr *", "*lchown *", "*lremovexattr *", "*lsetxattr *", "*removexattr *", "*setuid *", "*setgid *", "*setreuid *", "*setregid *", "*setcap *", "*chattr *") 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_common_process_for_elevation_control_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 execute this command. Please update the filter macros to remove false positives.
References:
  -https://attack.mitre.org/techniques/T1548/001/
  -https://github.com/Neo23x0/auditd/blob/master/audit.rules#L285-L297
  -https://github.com/bfuzzy1/auditd-attack/blob/master/auditd-attack/auditd-attack.rules#L269-L270
  -https://github.com/microsoft/MSTIC-Sysmon/blob/main/linux/configs/attack-based/privilege_escalation/T1548.001_ElevationControl_CommonProcesses.xml
drilldown_searches:
  :
tags:
  analytic_story:
    - 'Linux Persistence Techniques'
    - 'China-Nexus Threat Activity'
    - 'Linux Living Off The Land'
    - 'Salt Typhoon'
    - 'Linux Privilege Escalation'
  asset_type:Endpoint
  mitre_attack_id:
    - 'T1548.001'
  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/T1548.001/chmod_uid/sysmon_linux.log
  source: Syslog:Linux-Sysmon/Operational
  sourcetype: sysmon:linux
manual_test:None