Github Outside Collaborator Detected

 Original Source: [Sigma source]
Title: Github Outside Collaborator Detected
Status: test
Description:Detects when an organization member or an outside collaborator is added to or removed from a project board or has their permission level changed or when an owner removes an outside collaborator from an organization or when two-factor authentication is required in an organization and an outside collaborator does not use 2FA or disables 2FA.
References:
  -https://docs.github.com/en/organizations/keeping-your-organization-secure/managing-security-settings-for-your-organization/reviewing-the-audit-log-for-your-organization#audit-log-actions
  -https://docs.github.com/en/organizations/keeping-your-organization-secure/managing-two-factor-authentication-for-your-organization/requiring-two-factor-authentication-in-your-organization
Author: Muhammad Faisal (@faisalusuf)
Date: 2023-01-20
modified:None
Tags:
  • -'attack.privilege-escalation'
  • -'attack.persistence'
  • -'attack.collection'
  • -'attack.t1098.001'
  • -'attack.t1098.003'
  • -'attack.t1213.003'
Logsource:
  • product: github
  • service: audit
  • definition: Requirements: The audit log streaming feature must be enabled to be able to receive such logs. You can enable following the documentation here: https://docs.github.com/en/enterprise-cloud@latest/admin/monitoring-activity-in-your-enterprise/reviewing-audit-logs-for-your-enterprise/streaming-the-audit-log-for-your-enterprise#setting-up-audit-log-streaming
Detection:
  selection:
    action:
      -'org.remove_outside_collaborator'
      -'project.update_user_permission'

  condition:selection
Falsepositives:
  -Validate the actor if permitted to access the repo.
  -Validate the Multifactor Authentication changes.
Level: medium