GHSA-m28w-2pqf-7qgj
webpack-dev-server vulnerable to denial of service via a malformed Host or Origin header
At a glance
- Published
- Updated
- CVE
- CVE-2026-14631
- CVSS_V3
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Description
### Impact An unauthenticated peer that can reach the `webpack-dev-server` process can terminate it by sending either a normal HTTP request with a malformed `Host` header, or a WebSocket upgrade to the default `/ws` endpoint with a malformed `Origin` header. The malformed header triggers an uncaught exception in the host-validation path and crashes the dev server process. ### Patches Fixed in `webpack-dev-server` 5.2.6 by treating malformed `Host` and `Origin` header values as invalid rather than throwing (see [PR #5699](https://github.com/webpack/webpack-dev-server/pull/5699)). ### Workarounds Keep the dev server bound to `localhost` (the default) and do not expose it to untrusted networks.
Affected packages
| Package | Versions |
|---|---|
| npm · webpack-dev-server | introduced 0, fixed 5.2.6 |
References
- https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-m28w-2pqf-7qgj WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-14631 ADVISORY
- https://github.com/webpack/webpack-dev-server/pull/5699 WEB
- https://github.com/webpack/webpack-dev-server/commit/f21ed0f44aceb6132abb591ee8b60d770b6e489f WEB
- https://cna.openjsf.org/security-advisories.html WEB
- https://github.com/webpack/webpack-dev-server PACKAGE
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |