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1 vulnerability found for middie by fastify

CVE-2026-22031 (GCVE-0-2026-22031)
Vulnerability from cvelistv5
Published
2026-01-19 15:24
Modified
2026-01-20 14:45
CWE
  • CWE-177 - Improper Handling of URL Encoding (Hex Encoding)
Summary
@fastify/middie is the plugin that adds middleware support on steroids to Fastify. A security vulnerability exists in @fastify/middie prior to version 9.1.0 where middleware registered with a specific path prefix can be bypassed using URL-encoded characters (e.g., `/%61dmin` instead of `/admin`). While the middleware engine fails to match the encoded path and skips execution, the underlying Fastify router correctly decodes the path and matches the route handler, allowing attackers to access protected endpoints without the middleware constraints. Version 9.1.0 fixes the issue.
Impacted products
Vendor Product Version
fastify middie Version: < 9.1.0
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Show details on NVD website


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