Cloud Authenticator Device-Management API Abuse (Pass-ta-key)
Detects abuse of Google Cloud Authenticator device-management API calls associated with the Pass-ta-key attack, where an attacker-controlled key is introduced or a device is de-registered without a legitimate biometric/attestation ceremony. Covers device/register with keys/genpair, device/add_uv_key, and device/forget commands observed in cloud authenticator device-management event logs. To reduce false positives, device/add_uv_key and device/forget calls only alert when they lack an associated preceding hardware attestation or biometric ceremony event, and legitimate user-initiated new-device enrollment (following a known legitimate sign-in with a prior MFA/biometric ceremony on the requesting device) and legitimate account-recovery flows are excluded.
Microsoft Sentinel (KQL)

