Path Traversal in @Fastify/static
CVE-2026-18427
@fastify/static before version 10.1.3 contains an incomplete fix for a previous route guard bypass. The static file handler rejected only parent directory segments, but it did not canonicalize dot segments, duplicate slashes, encoded dots…
Vulnerability class: Path Traversal (Directory Traversal)
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
Affected products
- @Fastify/static — versions 0, 10.1.3
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-18427?
- CVE-2026-18427 is a high-severity vulnerability in @Fastify/static, classified under Path Traversal. CVSS score: 7.5/10. Published 2026-08-06.
- How severe is CVE-2026-18427?
- High severity. CVSS v3 base score is 7.5 out of 10.