CVE-2026-2880
HIGH EPSS 30.8%
Published Feb 27, 20264mo ago · Modified May 14, 20261mo ago
8.2 CVSS 4.0
Published Feb 27, 2026 4mo ago
Last Modified May 14, 2026 1mo ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
30.8% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-20 Improper Input Validation Validation
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| fastify | fastify\/middie | * | <9.2.0 |
References 1
- github.com https://github.com/fastify/middie/security/advisories/GHSA-8p85-9qpw-fwgw
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.