OpenAM OAuth Client Impersonation via JWKS Resolver Cache

Open Access Management (OpenAM) is an access management solution. Prior to 16.1.1, the private_key_jwt client authentication path uses ClientJwksResolverCache without reliably binding a cached jwks_uri resolver and verified assertion to the expected clientID in ClientCredentialsReader. An attacker controlling any registered client with published keys, including one obtained through open dynamic registration when enabled, can authenticate as another client whose keys are exposed through jwks_uri and mint tokens in that client's name across realms in the same OpenAM process. This issue is fixed in version 16.1.1.