cvedb.io
CVE-2026-2880
CRITICAL · CVSS 9.1
EPSS exploitation probability: 0%
Published 2026-02-27T19:16:12.807 · Last modified 2026-06-17T10:31:56.523

Summary

A vulnerability in @fastify/middie versions < 9.2.0 can result in authentication/authorization bypass when using path-scoped middleware (for example, app.use('/secret', auth)). When Fastify router normalization options are enabled (such as ignoreDuplicateSlashes, useSemicolonDelimiter, and related trailing-slash behavior), crafted request paths may bypass middleware checks while still being routed to protected handlers.

Affected products

fastify — fastify\/middie

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.