VULNERABILITY INTELLIGENCE

CVE-2026-6414

CVSS score5.9 MEDIUM
EPSS probability0.42%
CISA KEVNot currently listed
Published2026-04-16
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Description

@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.

Weakness classification

  • ce714d77-add3-4f53-aff5-83d477b104bb: CWE-177

Primary references