Google Cloud Service Account Disabled or Deleted — Sigma Rule

Rule metadata and linked tags

Author: Austin Songer @austinsonger. Source status: test; severity: medium. Source dates: 2021-08-14 / 2022-10-09.

{
  "product": "gcp",
  "service": "gcp.audit"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 611f4ca410957970175fc072602e3714d209a1b9c0ef68cf31e71ffe73703a3f

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: Google Cloud Service Account Disabled or Deleted
id: 13f81a90-a69c-4fab-8f07-b5bb55416a9f
status: test
description: Identifies when a service account is disabled or deleted in Google Cloud.
references:
    - https://cloud.google.com/iam/docs/reference/rest/v1/projects.serviceAccounts
author: Austin Songer @austinsonger
date: 2021-08-14
modified: 2022-10-09
tags:
    - attack.impact
    - attack.t1531
logsource:
    product: gcp
    service: gcp.audit
detection:
    selection:
        gcp.audit.method_name|endswith:
            - .serviceAccounts.disable
            - .serviceAccounts.delete
    condition: selection
falsepositives:
    - Service Account being disabled or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
    - Service Account disabled or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium

Original YAML and metadata in JSON

False positives

• Service Account being disabled or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
• Service Account disabled or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

Source references

• https://cloud.google.com/iam/docs/reference/rest/v1/projects.serviceAccounts