VULNERABILITY INTELLIGENCE

CVE-2026-2880

CVSS score9.1 CRITICAL
EPSS probability0.43%
CISA KEVNot currently listed
Published2026-02-27
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Description

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.

Weakness classification

  • ce714d77-add3-4f53-aff5-83d477b104bb: CWE-20

Primary references