Kernel module load via insmod

Detects the use of the insmod binary to load a Linux kernel object file. Threat actors can use this binary, given they have root privileges, to load a rootkit on a system providing them with complete control and the ability to hide from security products. Manually loading a kernel module in this manner should not be at all common and can indicate suspcious or malicious behavior.

Rule type: eql

Rule indices:

logs-*

Severity: medium

Risk score: 47

Runs every: 5m

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

Maximum alerts per execution: 100

References:

https://decoded.avast.io/davidalvarez/linux-threat-hunting-syslogk-a-kernel-rootkit-found-under-development-in-the-wild/

Tags:

Elastic
Host
Linux
Threat Detection
Persistence
Rootkit

Version: 100

Rule authors:

Elastic

Rule license: Elastic License v2

Rule query

edit

process where event.type == "start" and process.executable : "/usr/sbin/insmod" and process.args : "*.ko"

Framework: MITRE ATT&CK^TM

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/
Sub-technique:
- Name: Kernel Modules and Extensions
- ID: T1547.006
- Reference URL: https://attack.mitre.org/techniques/T1547/006/

« Suspicious File Creation in /etc for Persistence SoftwareUpdate Preferences Modification »