CVE-2026-14181 (GCVE-0-2026-14181)
Vulnerability from cvelistv5
Published
2026-07-01 11:42
Modified
2026-07-01 12:05
CWE
Summary
@fastify/middie versions 9.1.0 through 9.3.2 fail to guard the URL normalization step used by the standalone engine when incoming request paths contain malformed percent-encoded sequences. Inputs such as an incomplete percent escape or a truncated multibyte sequence cause the underlying decoder to throw synchronously, and the exception escapes the middie normalize step and terminates the Node.js process. The bypass affects applications that call middie.run directly on the standalone engine API, causing an immediate denial of service for all connected clients until restart. Applications using the Fastify plugin path are not affected because Fastifys error handler catches the exception. Patches: upgrade to @fastify/middie 9.3.3. Workarounds: migrate from the standalone engine API to the Fastify plugin path, where the framework error handler catches the exception.
Impacted products
Vendor Product Version
@fastify/middie @fastify/middie Version: 9.1.0   ≤
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Show details on NVD website


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