name: Linux Setuid Using Setcap Utility
id: 9d96022e-6250-11ec-9a19-acde48001122
version: 1
date: '2021-12-21'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: This analytic looks for suspicious setcap utility execution to enable
  SUID bit. This allows a user to temporarily gain root access, usually in order to
  run a program. For example, only the root account is allowed to change the password
  information contained in the password database; If the SUID bit appears as an s,
  the file's owner also has execute permission to the file; if it appears as an S,
  the file's owner does not have execute permission. The second specialty permission
  is the SGID, or set group id bit. It is similar to the SUID bit, except it can temporarily
  change group membership, usually to execute a program. The SGID bit is set if an
  s or an S appears in the group section of permissions.
data_source:
- Sysmon Event ID 1
search:
  selection1:
    CommandLine: '*setcap *'
  selection2:
    Image|endswith: setcap
  selection3:
    CommandLine: '* cap_setuid='
  condition: (selection1 or selection2) and selection3
how_to_implement: To successfully implement this search, you need to be ingesting
  logs with the process name, parent process, and command-line executions from your
  endpoints. If you are using Sysmon, you can use the Add-on for Linux Sysmon from
  Splunkbase.
known_false_positives: Administrator or network operator can execute this command.
  Please update the filter macros to remove false positives.
references:
- https://www.hackingarticles.in/linux-privilege-escalation-using-capabilities/
tags:
  analytic_story:
  - Linux Privilege Escalation
  - Linux Persistence Techniques
  asset_type: Endpoint
  confidence: 70
  impact: 70
  message: A commandline $process$ that may set suid or sgid on $dest$
  mitre_attack_id:
  - T1548.001
  - T1548
  observable:
  - name: dest
    type: Hostname
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  risk_score: 49
  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/linux_setcap/sysmon_linux.log
    source: Syslog:Linux-Sysmon/Operational
    sourcetype: sysmon:linux