CVE-2026-2880

9.1 CRITICAL
Published: February 27, 2026 Modified: March 19, 2026
View on NVD

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.

AI Explanation

Get an AI-powered plain-language explanation of this vulnerability and remediation steps.

Login to generate AI explanation

CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/fastify/middie/security/advisories/GHSA-8p85-9qpw-fwgw
Source: ce714d77-add3-4f53-aff5-83d477b104bb
Mitigation Vendor Advisory

1 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.1 / 10.0
EPSS (Exploit Probability)
0.2%
37th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

openjsf