10

CVE-2026-15631

@fastify/http-proxy vulnerable to prefix escape via WebSocket path traversal

Impact: @fastify/http-proxy versions from 9.4.0 up to and including 11.5.0 fail to validate the resolved WebSocket destination path against the configured rewrite prefix. The WebSocket routing path in WebSocketProxy.findUpstream resolves the destination via the WHATWG URL constructor, which collapses dot segments, so a crafted upgrade request with path traversal sequences can escape the rewrite prefix and reach upstream endpoints that were not meant to be exposed by the proxy. This is a variant of CVE-2021-21322 in a code path that never went through the HTTP fix in fastify/reply-from. Exploitation requires a non-normalizing WebSocket client, since browsers and the ws package normalize the request path before sending, but raw HTTP clients or downstream proxies that forward the request target unchanged make the attack reachable in production topologies. 

Patches: upgrade to @fastify/http-proxy 11.6.0. 

Workarounds: none.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Fastify ≫ Fastify/http-proxy SwPlatformnode.js Version >= 9.4.0 < 11.6.0
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.33% 0.251
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
NIST 10 3.9 5.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
ce714d77-add3-4f53-aff5-83d477b104bb 8.7 2.2 5.8
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

https://cna.openjsf.org/security-advisories.html
Vendor Advisory
https://github.com/fastify/fastify-http-proxy/security/advisories/GHSA-7hrw-592w-9wh2
Vendor Advisory