T1562.012SubTechniquedefense-evasionagent-callable

T1562.012Disable or Modify Linux Audit System

Sub-technique of T1562

Platforms: Linux

ATT&CK version: 14.1

What it is

Adversaries may disable or modify the Linux audit system to hide malicious activity and avoid detection. Linux admins use the Linux Audit system to track security-relevant information on a system. The Linux Audit system operates at the kernel-level and maintains event logs on application and system activity such as process, network, file, and login events based on pre-configured rules. Often referred to as `auditd`, this is the name of the daemon used to write events to disk and is governed by the parameters set in the `audit.conf` configuration file. Two primary ways to configure the log generation rules are through the command line `auditctl` utility and the file `/etc/audit/audit.rules`, containing a sequence of `auditctl` commands loaded at boot time.(Citation: Red Hat System Auditing)(Citation: IzyKnows auditd threat detection 2022) With root privileges, adversaries may be able to ensure their activity is not logged through disabling the Audit system service, editing the configuration/rule files, or by hooking the Audit system library functions. Using the command line, adversaries can disable the Audit system service through killing processes associated with `auditd` daemon or use `systemctl` to stop the Audit service. Adversaries can also hook Audit system functions to disable logging or modify the rules contained in the `/etc/audit/audit.rules` or `audit.conf` files to ignore malicious activity.(Citation: Trustwave Honeypot SkidMap 2023)(Citation: ESET Ebury Feb 2014)

ATT&CK tactics· 1

Defense Evasion

References

  1. https://attack.mitre.org/techniques/T1562/012
  2. https://izyknows.medium.com/linux-auditd-for-threat-detection-d06c8b941505
  3. https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/security_guide/chap-system_auditing
  4. https://www.welivesecurity.com/2014/02/21/an-in-depth-analysis-of-linuxebury/
  5. https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/honeypot-recon-new-variant-of-skidmap-targeting-redis/
Sourced from MITRE ATT&CK Enterprise v14.1. Curated and contextualized for EU compliance use cases by Adam Lundqvist, Founder at SQUR.