CVE-2026-2880

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/fastify/middie/security/advisories/GHSA-8p85-9qpw-fwgw

Configurations

No configuration.

History

02 Mar 2026, 20:30

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad en las versiones de @fastify/middie anteriores a la 9.2.0 puede resultar en una omisión de autenticación/autorización al usar middleware con ámbito de ruta (por ejemplo, app.use('/secret', auth)). Cuando las opciones de normalización del router de Fastify están habilitadas (como ignoreDuplicateSlashes, useSemicolonDelimiter y el comportamiento relacionado con las barras finales), las rutas de solicitud manipuladas pueden omitir las comprobaciones del middleware mientras siguen siendo enrutadas a manejadores protegidos.

27 Feb 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-27 19:16

Updated : 2026-03-02 20:30

NVD link : CVE-2026-2880

Mitre link : CVE-2026-2880

CVE.ORG link : CVE-2026-2880

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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