pac4j-jwt Security Restriction Bypass Vulnerability

A vulnerability has been identified in pac4j-jwt. A remote attacker could exploit this vulnerability to trigger security restriction bypass on the targeted system.

Note:

Proof of Concept exploit code Is publicly available for CVE-2026-29000. Attackers who possess the server's RSA public key can create a JWE-wrapped PlainJWT with arbitrary subject and role claims, bypassing signature verification to authenticate as any user including administrators. Hence, the risk level is rated as Medium Risk.