Fastify Jwt
Monthly
Key-based authorization bypass in @fastify/jwt before 10.2.2 permits any low-privileged authenticated user holding a token signed by the application's global secret to access routes explicitly restricted to a separate per-request key, silently crossing a cryptographic trust boundary. Applications implementing multi-domain JWT authorization - for example, separating user and admin token verification keys - are specifically at risk, as the plugin's option merge incorrectly applies the global key last, overriding the developer-supplied per-request key. No public exploit code has been identified and the vulnerability is not listed in the CISA KEV catalog, but the fix is available in version 10.2.2 and the attack path is mechanically straightforward for any authenticated user.
Key-based authorization bypass in @fastify/jwt before 10.2.2 permits any low-privileged authenticated user holding a token signed by the application's global secret to access routes explicitly restricted to a separate per-request key, silently crossing a cryptographic trust boundary. Applications implementing multi-domain JWT authorization - for example, separating user and admin token verification keys - are specifically at risk, as the plugin's option merge incorrectly applies the global key last, overriding the developer-supplied per-request key. No public exploit code has been identified and the vulnerability is not listed in the CISA KEV catalog, but the fix is available in version 10.2.2 and the attack path is mechanically straightforward for any authenticated user.