CSIRTS // UNIFIED SECURITY ADVISORY FEEDSYS ● ONLINE · POWERED BY INTELFUSIONS.COM

GHSA-83w8-p2f5-377r: @fastify/static vulnerable to route guard bypass via path traversal

highCVSS 7.5CVE-2026-15074
Impact @fastify/static is vulnerable to a bypass of route-based middleware and guards via non-leading .. and %2E%2E path segments. find-my-way does not normalize .. when matching routes, so a request such as /foo/../deep/secret.txt matches the static plugin's catch-all instead of the guarded /deep/*. The getPathnameForSend helper introduced by the fix for GHSA-x428-ghpx-8j92 only guards against the %2F variant; .. and %2E%2E survive the decodeURI + encodeURI round-trip and are then collapsed away by @fastify/send's path.normalize before its own traversal guard runs. Applications that rely on route-based middleware or guards to protect files served by @fastify/static can be bypassed with non-leading dot-dot path segments. Patches Upgrade to @fastify/static 10.1.1. Workarounds Do not use route-based middlewares or guards to protect files served by @fastify/static.

Details

Source
GitHub Security Advisories (INTL · database · site)
Severity
high — CVSS 7.5
Published
2026-07-24
Last updated
2026-07-24
Exploitation
Not in CISA KEV at last sync

Original advisory: https://github.com/advisories/GHSA-83w8-p2f5-377r

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Referenced CVEs

CVECSIRTS overviewExternal
CVE-2026-15074coverage & exploitation statusNVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

More from GitHub Security Advisories