HIGH SeverityCVSS 4.08.2CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

CVE-2026-2880

Last updated Feb 27, 2026 · Published Feb 27, 2026

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.

Affected products

1 listed

@fastify/middie:@fastify/middie

Mappings

CWE

CWE-20

CAPEC

None listed.