CVE-2026-114348 webpack-dev-server vulnerable to information disclosure via Host validation bypass in the open-editor endpoint
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-114348?
CVE-2026-114348 is a medium-severity vulnerability in webpack-dev-server, published on 22 Oct 2026.
Official description
webpack-dev-server is a development server that provides live reloading for webpack projects. In versions from 5.1.0 before 5.2.7 and in version 6.0.0, the unauthenticated open-editor endpoint validates the Host header with a regular expression meant for browser Origin schemes, so a Host value beginning with file: or with an extension scheme short-circuits the hostname and allowedHosts checks. A network peer that can reach the dev server can send a request with a malformed Host that passes validation and then causes the endpoint's URL construction to throw, and in the default non-production mode the server returns an HTTP 500 body containing the full exception stack trace, which discloses absolute filesystem paths, installed module locations, and internal source line numbers. The server keeps running, so there is no denial of service. The issue is fixed in webpack-dev-server 5.2.7 and 6.1.0, and users should upgrade to one of those versions or later.
Which versions are affected by CVE-2026-114348?
It affects 1 product.
Products include Webpack.js Webpack-Dev-Server.
How do I fix CVE-2026-114348?
No fix has been published for CVE-2026-114348 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-114348 being exploited?
There is no known exploitation of CVE-2026-114348 in the wild and no public exploit code.
Other vulnerabilities in webpack-dev-server
- CVE-2026-112085 webpack-dev-server vulnerable to cross-origin WebSocket access via proxied upgrades
- CVE-2018-14732 Missing Origin Validation in webpack-dev-server
- CVE-2025-30360 webpack-dev-server users' source code may be stolen when they access a malicious web site with non-Chromium based browser
- CVE-2026-14631 webpack-dev-server vulnerable to denial of service via a malformed Host or Origin header
- CVE-2026-9595 webpack-dev-server vulnerable to HMR WebSocket interception via permissive user proxies
Sources
Also known as GHSA-wqhc-fvfg-56q6, UBUNTU-CVE-2026-114348.