Apache CXF: Authentication Bypass in OAuth2 TokenIntrospectionService

CVE-2026-50623

What is CVE-2026-50623?

An authentication bypass vulnerability exists in the OAuth2 TokenIntrospectionService in Apache CXF. Due to a missing 'throw' keyword in the security context check, the introspection endpoint (/services/oauth2/introspect) can be accessed by any unauthenticated network attacker. However note that this is a safeguard only in the case that someone forgot to enable authentication on the service. Users are recommended to upgrade to version 4.2.2 or 4.1.7, which fixes this issue.

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