CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:NCVE-2026-6414
Medium (5.9) in fastify fastify-static. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in @fastify/static 9.1.1.
@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
- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 36% of CVEs (scores of 2026-10-31)
- CWE
- CWE-177
- Published
- Modified
- Record from
- the NVD, synced
Affected
- fastify:fastify-static
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-x428-ghpx-8j92 | npm | @fastify/static | >=8.0.0 <9.1.1 | 9.1.1 |