name: Linux Setuid Using Setcap Utility
id: 9d96022e-6250-11ec-9a19-acde48001122
version: 1
date: '2021-12-21'
author: Teoderick Contreras, Splunk
type: Anomaly
datamodel:
- Endpoint
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.
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where (Processes.process_name = setcap
  OR Processes.process = "*setcap *") AND Processes.process IN ("* cap_setuid=ep *",
  "* cap_setuid+ep *", "* cap_net_bind_service+p *", "* cap_net_raw+ep *", "* cap_dac_read_search+ep
  *") 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_setuid_using_setcap_utility_filter`'
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
  automated_detection_testing: passed
  cis20:
  - CIS 3
  - CIS 5
  - CIS 16
  confidence: 70
  context:
  - Source:Endpoint
  - Stage:Privilege Escalation
  - Stage:Persistence
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548.001/linux_setcap/sysmon_linux.log
  impact: 70
  kill_chain_phases:
  - Exploitation
  message: A commandline $process$ that may set suid or sgid on $dest$
  mitre_attack_id:
  - T1548.001
  - T1548
  nist:
  - DE.CM
  observable:
  - name: dest
    type: Hostname
    role:
    - Victim
  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: 49
  security_domain: endpoint
  asset_type: Endpoint