IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.

« Kerberos Traffic from Unusual Process Kernel module load via insmod »

› › ›

Kernel Module Removal

edit

Kernel Module Removal

edit

Kernel modules are pieces of code that can be loaded and unloaded into the kernel upon demand. They extend the functionality of the kernel without the need to reboot the system. This rule identifies attempts to remove a kernel module.

Rule type: query

Rule indices:

auditbeat-*
logs-endpoint.events.*

Severity: high

Risk score: 73

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

http://man7.org/linux/man-pages/man8/modprobe.8.html

Tags:

Elastic
Host
Linux
Threat Detection
Defense Evasion

Version: 8 (version history)

Added (Elastic Stack release): 7.8.0

Last modified (Elastic Stack release): 8.4.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positives

edit

There is usually no reason to remove modules, but some buggy modules require it. These can be exempted by username. Note that some Linux distributions are not built to support the removal of modules at all.

Rule query

edit

event.category:process and event.type:(start or process_started) and
process.args:((rmmod and sudo) or (modprobe and sudo and ("--remove"
or "-r")))

Threat mapping

edit

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
Technique:
- Name: Impair Defenses
- ID: T1562
- Reference URL: https://attack.mitre.org/techniques/T1562/
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
Technique:
- Name: Boot or Logon Autostart Execution
- ID: T1547
- Reference URL: https://attack.mitre.org/techniques/T1547/

Rule version history

edit

Version 8 (8.4.0 release)

Formatting only

Version 7 (7.12.0 release)

Formatting only

Version 6 (7.11.2 release)

Formatting only

Version 5 (7.11.0 release)

Formatting only

Version 4 (7.10.0 release)

Formatting only

Version 3 (7.9.1 release)

Formatting only

Version 2 (7.9.0 release)

Updated query, changed from:

event.action:executed and process.args:(rmmod and sudo or modprobe and
sudo and ("--remove" or "-r"))

« Kerberos Traffic from Unusual Process Kernel module load via insmod »