New attack technique: Backdoor a GCS Bucket via Overly Permissive IAM Policy (gcp.exfiltration.backdoor-gcs-bucket)

[Minosity-VR]

What does this PR do?

New attack technique: gcp.exfiltration.backdoor-gcs-bucket

Motivation

GCP parity with existing AWS attack techniques.

Test results

• stratus detonate gcp.exfiltration.backdoor-gcs-bucket
• storage.setIamPermissions appears in GCP Data Access audit logs

Checklist

• The attack technique emulates a single attack step, not a full attack chain
• We have factual evidence & references that the attack technique was used by real malware, pentesters, or attackers
• The attack technique makes no assumption about the state of the environment prior to warming it up