:: Deepquest ::

HashiCorp Vault’s GCP authentication method can be bypassed on gce type roles that do not specify bound_service_accounts. Vault does not enforce that the compute_engine data in a signed JWT token has any relationship to the service account that created the token. This makes it possible to impersonate arbitrary GCE instances, by creating a JWT token with a faked compute_engine struct, using an arbitrary attacker controlled service account.