CVE-2026-15074

@fastify/static up to and including version 10.1.0 fails to reject dot-dot path segments in request pathnames before the file-resolution stage. This is a bypass of the earlier fix for CVE-2026-6414, which only covered encoded forward slashes. Because the underlying send library normalizes dot segments before applying its own path-traversal guard, an unauthenticated attacker can bypass any route-scoped middleware and read files inside the static root that live under the guarded URL prefix. The bypass does not allow access outside the configured static root by itself, it defeats route-guard filtering only. The issue is patched in @fastify/static 10.1.1.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cna.openjsf.org/security-advisories.html	Vendor Advisory
https://github.com/fastify/fastify-static/security/advisories/GHSA-83w8-p2f5-377r	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:fastify:fastify-static:*:*:*:*:*:*:*:*

History

28 Jul 2026, 17:02

Type	Values Removed	Values Added
CPE		cpe:2.3:a:fastify:fastify-static::::::::
References	~~() https://cna.openjsf.org/security-advisories.html -~~	() https://cna.openjsf.org/security-advisories.html - Vendor Advisory
References	~~() https://github.com/fastify/fastify-static/security/advisories/GHSA-83w8-p2f5-377r -~~	() https://github.com/fastify/fastify-static/security/advisories/GHSA-83w8-p2f5-377r - Vendor Advisory
First Time		Fastify Fastify fastify-static

23 Jul 2026, 04:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-23 04:16

Updated : 2026-07-28 17:02

NVD link : CVE-2026-15074

Mitre link : CVE-2026-15074

CVE.ORG link : CVE-2026-15074

JSON object : View

Products Affected

fastify

fastify-static

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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