CVE-2026-6414
MEDIUMCVSS v3.1: 5.9
Source data as of:
At a glance
- Severity
- MEDIUM
- CVSS
- 5.9 v3.1 · NVD
- EPSS
- EPSS not provided by FIRST.org for this CVE
- CISA KEV
- No
- Attack conditions (CVSS vector)
- NetworkNo privilegesNo user interaction · Source: NVD Vector
- Published
- 2026-04-16 · Modified: 2026-04-16
- References
- Jump to references (4)
CVSS / EPSS / KEV
Source — CVSS: NVD · EPSS: FIRST.org · KEV: CISA. Data & Sources
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.
References
Reference URLs as listed by NVD, grouped by a mechanical match on the link's host/pattern. Labels describe the link type only.
- Vendor advisory https://cna.openjsf.org/security-advisories.html
- Vendor advisory https://github.com/fastify/fastify-static/security/advisories/GHSA-x428-ghpx-8j92
- Vendor advisory https://github.com/fastify/middie/security/advisories/GHSA-cxrg-g7r8-w69p
- Vendor advisory https://github.com/honojs/hono/security/advisories/GHSA-q5qw-h33p-qvwr