CVE-2026-6414 (GCVE-0-2026-6414)
Vulnerability from cvelistv5 – Published: 2026-04-16 13:09 – Updated: 2026-04-16 13:48
VLAI
EPSS
VEX
Title
@fastify/static vulnerable to route guard bypass via encoded path separators
Summary
@fastify/static versions 8.0.0 through 9.1.0 decode percent-encoded path separators (%2F) before filesystem resolution, while Fastify's router treats them as literal characters. This mismatch allows attackers to bypass route-based middleware or guards that protect files served by @fastify/static. For example, a route guard on a protected path can be circumvented by encoding the path separator in the URL. Upgrade to @fastify/static 9.1.1 to fix this issue. There are no workarounds.
Severity
5.9 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-16 13:48 UTC
CWE
- CWE-177 - Improper Handling of URL Encoding (Hex Encoding)
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| @fastify/static | @fastify/static |
Affected:
8.0.0 , < 9.1.1
(semver)
Unaffected: 9.1.1 (semver) |
guessed |
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