A flaw in Keystone’s credential creation endpoint allows an attacker who holds an unrestricted application credential for one project to create an EC2 credential that targets another project. Because the service does not verify that the supplied project_id matches the authenticating credential’s project, the resulting token can be scoped to the target project while the original application credential identifier is retained. This authentication/authorization weakness (CWE‑863) enables an attacker to move laterally between projects within the same role footprint, granting unauthorized access to resources, potentially compromising confidentiality, integrity, and availability.

OpenStack Keystone versions 13 through 29 are vulnerable. The issue affects all deployments of the Keystone identity service that use the POST /v3/credentials API without additional policy checks.

The vulnerability scores a CVSS of 7.9, indicating high severity. No EPSS data is available, and it is not listed in the CISA KEV catalog. The attack can be performed by any user possessing an unrestricted application credential, simply by submitting a crafted POST request to /v3/credentials. No special network conditions are required, making the risk realistic in environments that allow unrestricted application credentials.