CyberRota Analysis
This is a critical severity vulnerability with a CVSS score of 9.0. See the original NVD description below for full technical details.
Original NVD Description
Cloud Foundry UAA incorrectly treated XML encryption to the Service Provider (confidentiality) as a substitute for XML signatures from the Identity Provider (authenticity) in two SAML flows: the OAuth 2.0 SAML2 bearer grant (token endpoint) and browser SSO (ACS) when wantAssertionSigned is set to false. Assertions or responses that were unsigned but contained encrypted content could still be accepted. Encryption uses the SP's public key from published metadata, therefore, any party, not only a trusted IdP, can produce ciphertext UAA can decrypt; successful decryption therefore does not prove the IdP issued the message. Affected versions: Cloud Foundry UAA (uaa_release) 2.0.0 through 78.13.0. Cloud Foundry CF Deployment all versions through 56.1.0.