CVE-2026-33807 (GCVE-0-2026-33807)
Vulnerability from cvelistv5
Published
2026-04-15 09:52
Modified
2026-04-15 13:09
Severity ?
CWE
  • CWE-436 - Interpretation Conflict
Summary
@fastify/express v4.0.4 and earlier contains a path handling bug in the onRegister function that causes middleware paths to be doubled when inherited by child plugins. When a child plugin is registered with a prefix that matches a middleware path, the middleware path is prefixed a second time, causing it to never match incoming requests. This results in complete bypass of Express middleware security controls, including authentication, authorization, and rate limiting, for all routes defined within affected child plugin scopes. No special configuration or request crafting is required. Upgrade to @fastify/express v4.0.5 or later.
Impacted products
Vendor Product Version
fastify @fastify/express Version: 0   
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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