Persistence Via Sudoers Files

testmedium
log source: linux · file_eventauthor Nasreddine Bencherchali (Nextron Systems)date 2022-07-05
01

description

What this is, in brief.

Detects the creation or modification of the main "/etc/sudoers" file or files within the "/etc/sudoers.d/" directory on Linux systems. Adversaries may alter sudoers configuration to execute commands with elevated privileges without supplying a password.

02

tags

attack.privilege-escalationattack.persistenceattack.t1548.003
03

rule source (YAML)

title: Persistence Via Sudoers Files
id: ddb26b76-4447-4807-871f-1b035b2bfa5d
status: test
description: |
    Detects the creation or modification of the main "/etc/sudoers" file or files within the "/etc/sudoers.d/" directory on Linux systems.
    Adversaries may alter sudoers configuration to execute commands with elevated privileges without supplying a password.
references:
    - https://www.sudo.ws/docs/man/sudoers.man/
    - https://github.com/h3xduck/TripleCross/blob/1f1c3e0958af8ad9f6ebe10ab442e75de33e91de/apps/deployer.sh
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-07-05
modified: 2026-08-15
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1548.003
logsource:
    product: linux
    category: file_event
detection:
    selection:
        - TargetFilename: '/etc/sudoers'
        - TargetFilename|startswith: '/etc/sudoers.d/'
    filter_main_dpkg:
        Image|endswith: '/usr/bin/dpkg'
        TargetFilename: '/etc/sudoers.d/README.dpkg-new'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Legitimate sudoers changes by administrators or configuration-management tools
level: medium
04

detects techniques (1)

ATT&CK techniques this enables or maps to.

05

references

External citations — patches, advisories, analysis.