Suspicious Google Cloud Function Create or Update Triggering Build

ATT&CK techniques

Initial Access → Defense Evasion

Recon
Resource Dev
Initial Access
- T1078.004Cloud Accounts
Execution
- T1651Cloud Administration Command
Persistence
- T1078.004Cloud Accounts
Priv Esc
- T1078.004Cloud Accounts
Defense Evasion
- T1078.004Cloud Accounts
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation or modification of a Google Cloud Function which automatically triggers a build using the default Cloud Build service account. Talos observed this serverless attack vector where an actor deploys a malicious function to execute attacker code during the build and inherit the over-privileged build service account, so unexpected function writes warrant review as a privilege-escalation foothold.

Reporting behind it

Related detections9 linkedT1078.004 — drag to rearrange

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Suspicious Cloud Sign-In From an Anonymizer or High-Risk Session (via signinlogs)

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Suspicious Google Cloud Function Create or Update Triggering Build

Pivot detection · T1078.004 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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