In Apache CXF's OAuth2 Dynamic Client Registration endpoint, the authorization server accepts and stores the scope value supplied in the client registration request verbatim, without validating it against an AS-defined allowlist. This could lead to a client self-assigning privileged scopes at registration time. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

Apache CXF's JwtRequestCodeFilter copies all claims from a signed request JWT into the authorization parameter map without excluding security-sensitive parameters. A client that can produce a validly-signed request JWT (e.g., one whose clientsecret is known or compromised) can thereby substitute the codechallenge, codechallengemethod, nonce, and state values that were set in the outer HTTP request, undermining PKCE integrity and OpenID Connect replay protection. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

Apache CXF’s OIDC relying-party token validation could accept self-issued ID tokens without enforcing required claim checks (issuer/subject/audience/time and subjwk binding), enabling authentication bypass with crafted tokens. However, note that self-issued ID tokens are not accepted by default in the validator. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fixes this issue.

In Apache CXF's DefaultEncryptingCodeDataProvider, a captured authorization code can be redeemed an unlimited number of times due to a flaw in the implementation of the removeCodeGrant functionality. This violates the RFC requirement that "The authorization code MUST NOT be used more than once." Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

Apache CXF's JMS transport deserializes the body of any inbound JMS ObjectMessage using native Java deserialization, with no type restrictions in place. Any attacker able to place a message on the service's JMS destination can submit a malicious serialized object, leading to denial of service or, if a suitable gadget class is on the classpath, remote code execution. The fix disables ObjectMessage deserialization by default, with a configuration switch to re-enable it if needed. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

An LDAP injection vulnerability in the LDAP Certificate repository of the XKMS server in Apache CXF may allow an attacker to retrieve arbitrary certificates from the repository. Users are recommended to upgrade to versions 4.2.1, 4.1.6 or 3.6.11, which fix this issue.

If untrusted users are allowed to configure JMS for Apache CXF, previously they could use RMI or LDAP URLs, potentially leading to code execution capabilities. This interface is now restricted to reject those protocols, removing this possibility.

Users are recommended to upgrade to versions 3.6.8, 4.0.9 or 4.1.3, which fix this issue.

A SSRF vulnerability in WADL service description in versions of Apache CXF before 4.0.5, 3.6.4 and 3.5.9 allows an attacker to perform SSRF style attacks on REST webservices. The attack only applies if a custom stylesheet parameter is configured.

A SSRF vulnerability using the Aegis DataBinding in versions of Apache CXF before 4.0.4, 3.6.3 and 3.5.8 allows an attacker to perform SSRF style attacks on webservices that take at least one parameter of any type. Users of other data bindings (including the default databinding) are not impacted.