# CVE-2026-6414

> Vulnerability · severity: **MEDIUM** (CVSS 5.9).

## 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.

## Key facts

- **CVE ID:** CVE-2026-6414
- **Published:** 2026-04-16
- **CVSS severity:** MEDIUM
- **CVSS base score:** 5.9
- **CWE codes:** CWE-177

## Affected products

- `fastify:fastify-static`

## Primary sources

- NIST NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-6414

## Citation

> AI Analytics. CVE-2026-6414. Retrieved 2026-07-19 from https://api.ai-analytics.org/cve/CVE-2026-6414. Derived from NIST NVD. Licensed CC0.

---

*[Dataset catalog](https://api.ai-analytics.org/datasets/) · [AI Analytics](https://api.ai-analytics.org/) · CC0 1.0*