CVE-2026-22037 @fastify/express vulnerable to Improper Handling of URL Encoding (Hex Encoding)

The @fastify/express plugin adds full Express compatibility to Fastify. A security vulnerability exists in @fastify/express prior to version 4.0.3 where middleware registered with a specific path prefix can be bypassed using URL-encoded characters e.g., /%61dmin instead of /admin. While the...

CVE-2026-22037: Improper Handling of URL Encoding (Hex Encoding)

The @fastify/express plugin adds full Express compatibility to Fastify. A security vulnerability exists in @fastify/express prior to version 4.0.3 where middleware registered with a specific path prefix can be bypassed using URL-encoded characters e.g., /%61dmin instead of /admin. While the...

@fastify/express security vulnerability

@fastify/express is a compatibility plugin developed by Fastify. Versions of @fastify/express prior to 4.0.3 contained security vulnerabilities. These vulnerabilities were caused by improper path prefix matching, which could allow middleware to bypass security checks...

PT-2026-3452

Name of the Vulnerable Software and Affected Versions @fastify/express versions prior to 4.0.3 Description A security issue exists in the @fastify/express plugin, which provides Express compatibility for Fastify. The problem occurs when middleware is registered with a specific path prefix...