AWS Console GetSigninToken Potential Abuse — Sigma Rule

Rule metadata and linked tags

Author: Chester Le Bron (@123Le_Bron). Source status: test; severity: medium. Source dates: 2024-02-26 / not supplied.

{
  "product": "aws",
  "service": "cloudtrail"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: c924ecf34bed246d1729a72104656c75242c8497251717b83b47f8e1dc7ee1cb

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: AWS Console GetSigninToken Potential Abuse
id: f8103686-e3e8-46f3-be72-65f7fcb4aa53
status: test
description: |
    Detects potentially suspicious events involving "GetSigninToken".
    An adversary using the "aws_consoler" tool can leverage this console API to create temporary federated credential that help obfuscate which AWS credential is compromised (the original access key) and enables the adversary to pivot from the AWS CLI to console sessions without the need for MFA using the new access key issued in this request.
references:
    - https://github.com/NetSPI/aws_consoler
    - https://www.crowdstrike.com/blog/analysis-of-intrusion-campaign-targeting-telecom-and-bpo-companies/
author: Chester Le Bron (@123Le_Bron)
date: 2024-02-26
tags:
    - attack.lateral-movement
    - attack.t1021.007
    - attack.t1550.001
logsource:
    product: aws
    service: cloudtrail
detection:
    selection:
        eventSource: 'signin.amazonaws.com'
        eventName: 'GetSigninToken'
    filter_main_console_ua:
        userAgent|contains: 'Jersey/${project.version}'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - GetSigninToken events will occur when using AWS SSO portal to login and will generate false positives if you do not filter for the expected user agent(s), see filter. Non-SSO configured roles would be abnormal and should be investigated.
level: medium

Original YAML and metadata in JSON

False positives

• GetSigninToken events will occur when using AWS SSO portal to login and will generate false positives if you do not filter for the expected user agent(s), see filter. Non-SSO configured roles would be abnormal and should be investigated.

Source references

• https://github.com/NetSPI/aws_consoler
• https://www.crowdstrike.com/blog/analysis-of-intrusion-campaign-targeting-telecom-and-bpo-companies/