A vulnerability allows users authenticating through a federated OIDC provider to obtain the uaa.admin scope despite operators restricting that provider through externalGroupsWhitelist configuration. The issue occurs specifically when an OIDC identity provider uses groupMappingMode: AS_SCOPES with a wildcard externalGroupsWhitelist entry.

Improper handling of case sensitivity (CWE-178) in the identity zone authorization check in the Identity Zone Endpoint in Cloud Foundry UAA allows a remote authenticated attacker holding only the zones.write authority to bypass the intended restriction that this authority does not grant access to the privileged uaa (system) identity zone, by referring to the zone identifier in a non-lowercase form (e.g. UAA) in the request path and body. The authorization layer performs a case-sensitive comparison against the system zone identifier, while the underlying MySQL persistence layer resolves identifiers case-insensitively under its default collation, so the request is authorized incorrectly and is then resolved against the real system zone record. This allows the attacker to overwrite the system zone's JWT signing key with attacker-controlled key material, forge JWTs claiming the admin client and administrator scopes, and fully compromise UAA and any Cloud Foundry deployment that trusts it. This issue only affects UAA deployments backed by MySQL using its default collation; PostgreSQL and HSQLDB backends are not affected.

A network attacker positioned between UAA and its LDAP directory can impersonate the directory using any certificate from any trusted CA, then harvest the LDAP bind password and every end-user password sent during simple-bind authentication, and return forged group memberships that grant themselves admin scopes. This affects every deployment that authenticates users against LDAP over StartTLS. Affected versions: UAA versions prior to v78.13.0; Cf-deployment versions prior to v56.2.0.

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.