CVE-2026-6414 (GCVE-0-2026-6414)

Vulnerability from cvelistv5 – Published: 2026-04-16 13:09 – Updated: 2026-04-16 13:48
VLAI?
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)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-177 - Improper Handling of URL Encoding (Hex Encoding)
Assigner
References
Impacted products
Vendor Product Version
@fastify/static @fastify/static Affected: 8.0.0 , < 9.1.1 (semver)
Unaffected: 9.1.1 (semver)
Create a notification for this product.
Credits
blakeembrey mcollina UlisesGascon climba03003
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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