CVE-2026-112712 (GCVE-0-2026-112712)
Vulnerability from cvelistv5
Published
2026-10-20 20:43
Modified
2026-10-30 17:17
Severity ?
CWE
  • CWE-436 - Interpretation Conflict
Summary
@fastify/middie is the Express-style middleware engine for Fastify. In versions from 9.0.0 through 9.3.5, the use() function joined a path-scoped middleware's mount path to the plugin scope prefix in a way that could diverge from the path Fastify's router serves, most often when the scope prefix ended in a slash, and also for array mount paths and for mount paths written without a leading slash. When the two paths disagreed, the middleware was silently skipped while the route handler still ran, so path-scoped middleware such as authentication, authorization, or rate limiting could be bypassed by a single unauthenticated request. The issue is fixed in @fastify/middie 9.3.6, and users should upgrade to 9.3.6 or later. As a workaround, enforce authorization in a Fastify hook such as preHandler that runs after the router has resolved the request.
Impacted products
Vendor Product Version
@fastify/middie @fastify/middie Version: 9.0.0   ≤
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Show details on NVD website


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