CVE-2026-85184 (GCVE-0-2026-85184)
Vulnerability from cvelistv5 – Published: 2026-09-04 09:15 – Updated: 2026-09-04 19:36
VLAI
EPSS
VEX
Title
@fastify/middie vulnerable to path-scoped middleware bypass via absolute-form request target
Summary
@fastify/middie versions >= 9.1.0 and before 9.3.4 decide whether to run path-scoped middleware by matching against the raw request target, while the Fastify router resolves an absolute-form request target to its path before dispatching. Because the two layers evaluate different strings, a request using an absolute-form target reaches the route handler while the path-scoped middleware, such as authentication or authorization, is skipped. An unauthenticated network attacker can use this to bypass path-based access controls in a Fastify application that relies on middie for those controls. Users should upgrade to @fastify/middie 9.3.4 or later.
Severity
9.1 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-04 19:36 UTC
CWE
- CWE-436 - Interpretation Conflict
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| @fastify/middie | @fastify/middie |
Affected:
9.1.0 , < 9.3.4
(semver)
Unaffected: 9.3.4 (semver) |
guessed |
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