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splunk-security_content/detections/endpoint/linux_auditd_setuid_using_setcap_utility.yml
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YAML

name: Linux Auditd Setuid Using Setcap Utility
id: 1474459a-302b-4255-8add-d82f96d14cd9
version: 6
date: '2025-05-02'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects the execution of the 'setcap' utility
to enable the SUID bit on Linux systems. It leverages Linux Auditd data, focusing
on process names and command-line arguments that indicate the use of 'setcap' with
specific capabilities. This activity is significant because setting the SUID bit
allows a user to temporarily gain root access, posing a substantial security risk.
If confirmed malicious, an attacker could escalate privileges, execute arbitrary
commands with elevated permissions, and potentially compromise the entire system.
data_source:
- Linux Auditd Execve
search: '`linux_auditd` execve_command IN ("*setcap *") AND execve_command IN ("*cap_setuid+ep*", "*cap_setuid=ep*", "*cap_net_bind_service+p*", "*cap_net_raw+ep*", "*cap_dac_read_search+ep*")
| rename host as dest
| rename comm as process_name
| rename exe as process
| stats count min(_time) as firstTime max(_time) as lastTime by argc execve_command dest
| `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
| `linux_auditd_setuid_using_setcap_utility_filter`'
how_to_implement: To implement this detection, the process begins by ingesting auditd
data, that consists of SYSCALL, TYPE, EXECVE and PROCTITLE events, which captures
command-line executions and process details on Unix/Linux systems. These logs should
be ingested and processed using Splunk Add-on for Unix and Linux (https://splunkbase.splunk.com/app/833),
which is essential for correctly parsing and categorizing the data. The next step
involves normalizing the field names to match the field names set by the Splunk
Common Information Model (CIM) to ensure consistency across different data sources
and enhance the efficiency of data modeling. This approach enables effective monitoring
and detection of linux endpoints where auditd is deployed
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/
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: A [$execve_command$] event occurred on host - [$dest$] to set the SUID or
SGID bit on files using the setcap utility.
risk_objects:
- field: dest
type: system
score: 81
threat_objects: []
tags:
analytic_story:
- Linux Privilege Escalation
- Linux Persistence Techniques
- Compromised Linux Host
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/linux_auditd_setuid/auditd_execve_setcap.log
source: auditd
sourcetype: auditd