Linux APT Privilege Escalation

Original Source: [splunk source]
Name:Linux APT Privilege Escalation
id:4d5a05fa-77d9-4fd0-af9c-05704f9f9a88
version:8
date:2025-02-10
author:Gowthamaraj Rajendran, Splunk
status:production
type:Anomaly
Description:The following analytic detects the use of the Advanced Package Tool (APT) with elevated privileges via sudo on Linux systems. It leverages Endpoint Detection and Response (EDR) telemetry to identify processes where APT commands are executed with sudo rights. This activity is significant because it indicates a user can run system commands as root, potentially leading to unauthorized root shell access. If confirmed malicious, this could allow an attacker to escalate privileges, execute arbitrary commands, and gain full control over the affected system, posing a severe security risk.
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="*apt*" AND Processes.process="*APT::Update::Pre-Invoke::*" AND Processes.process="*sudo*" 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_apt_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 may be present, filter as needed.
References:
  -https://gtfobins.github.io/gtfobins/apt/
  -https://www.digitalocean.com/community/tutorials/what-is-apt
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
  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/apt/sysmon_linux.log
  source: Syslog:Linux-Sysmon/Operational
  sourcetype: sysmon:linux
manual_test:None