Potential Linux Amazon SSM Agent Hijacking — Sigma Rule

Rule metadata and linked tags

Author: Muhammad Faisal. Source status: test; severity: medium. Source dates: 2023-08-03 / not supplied.

{
  "category": "process_creation",
  "product": "linux"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: a9dbff5d3f7c4f8b0087f97d07fc8bcd7a5713b45ae5a141e9e34b9a0f07dbd7

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Potential Linux Amazon SSM Agent Hijacking
id: f9b3edc5-3322-4fc7-8aa3-245d646cc4b7
status: test
description: Detects potential Amazon SSM agent hijack attempts as outlined in the Mitiga research report.
references:
    - https://www.mitiga.io/blog/mitiga-security-advisory-abusing-the-ssm-agent-as-a-remote-access-trojan
    - https://www.bleepingcomputer.com/news/security/amazons-aws-ssm-agent-can-be-used-as-post-exploitation-rat-malware/
    - https://www.helpnetsecurity.com/2023/08/02/aws-instances-attackers-access/
author: Muhammad Faisal
date: 2023-08-03
tags:
    - attack.command-and-control
    - attack.persistence
    - attack.t1219.002
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/amazon-ssm-agent'
        CommandLine|contains|all:
            - '-register '
            - '-code '
            - '-id '
            - '-region '
    condition: selection
falsepositives:
    - Legitimate activity of system administrators
level: medium

Original YAML and metadata in JSON

False positives

• Legitimate activity of system administrators

Source references

• https://www.mitiga.io/blog/mitiga-security-advisory-abusing-the-ssm-agent-as-a-remote-access-trojan
• https://www.bleepingcomputer.com/news/security/amazons-aws-ssm-agent-can-be-used-as-post-exploitation-rat-malware/
• https://www.helpnetsecurity.com/2023/08/02/aws-instances-attackers-access/