OpenStack Keystone versions before 26.0.1, between 27.0.0.0rc1 and 27.0.0, and between 28.0.0.0rc1 and 28.0.0 allow requests to /v3/ec2tokens or /v3/s3tokens endpoints with a valid AWS Signature to obtain Keystone authorization improperly. This vulnerability is identified as CVE-2025-65073 and has a high severity score of 7.5. Fixed versions include 26.0.1, 27.0.0, and 28.0.0.