Kernel Module Removal

Last updated 5 months ago on 2025-03-20

Created 5 years ago on 2020-04-24

About

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.

Tags

Domain: EndpointOS: LinuxUse Case: Threat DetectionTactic: Defense EvasionData Source: Elastic EndgameData Source: Elastic DefendData Source: CrowdstrikeData Source: SentinelOneLanguage: eql

Severity

medium

Risk Score

MITRE ATT&CK™

Defense Evasion (TA0005)(opens in a new tab or window)

↳ Impair Defenses (T1562)(opens in a new tab or window)

Persistence (TA0003)(opens in a new tab or window)

↳ Boot or Logon Autostart Execution (T1547)(opens in a new tab or window)

False Positive Examples

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.

License

Elastic License v2(opens in a new tab or window)

Definition

Rule Type

Event Correlation Rule

Integration Pack

Prebuilt Security Detection Rules

Index Patterns

endgame-*logs-crowdstrike.fdr*logs-endpoint.events.process*logs-sentinel_one_cloud_funnel.*

Related Integrations

endpoint(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

Query

process where host.os.type == "linux" and event.type == "start" and
  event.action in ("exec", "exec_event", "start", "ProcessRollup2") and
  (
    process.name == "rmmod" or
    (process.name == "modprobe" and process.args in ("--remove", "-r"))
  ) and
  process.parent.name in ("sudo", "bash", "dash", "ash", "sh", "tcsh", "csh", "zsh", "ksh", "fish")

Install detection rules in Elastic Security

Detect Kernel Module Removal in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).