GCP Logging Bucket Deletion

edit

Identifies a Logging bucket deletion in Google Cloud Platform (GCP). Log buckets are containers that store and organize log data. A deleted bucket stays in a pending state for 7 days, and Logging continues to route logs to the bucket during that time. To stop routing logs to a deleted bucket, the log sinks can be deleted that have the bucket as a destination, or the filter for the sinks can be modified to stop routing logs to the deleted bucket. An adversary may delete a log bucket to evade detection.

Rule type: query

Rule indices:

  • filebeat-*
  • logs-gcp*

Severity: medium

Risk score: 47

Runs every: 5 minutes

Searches indices from: now-6m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Cloud
  • GCP
  • Continuous Monitoring
  • SecOps
  • Log Auditing

Version: 4 (version history)

Added (Elastic Stack release): 7.10.0

Last modified (Elastic Stack release): 7.12.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positives

edit

Logging bucket deletions may be done by a system or network administrator. Verify whether the user email, resource name, and/or hostname should be making changes in your environment. Logging bucket deletions from unfamiliar users or hosts should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

Investigation guide

edit

The GCP Filebeat module must be enabled to use this rule.

Rule query

edit
event.dataset:(googlecloud.audit or gcp.audit) and
event.action:google.logging.v*.ConfigServiceV*.DeleteBucket and
event.outcome:success

Threat mapping

edit

Framework: MITRE ATT&CKTM

Rule version history

edit
Version 4 (7.12.0 release)
  • Formatting only
Version 3 (7.11.2 release)
  • Formatting only
Version 2 (7.11.0 release)
  • Updated query, changed from:

    event.dataset:googlecloud.audit and
    event.action:google.logging.v*.ConfigServiceV*.DeleteBucket and
    event.outcome:success