Description
webpack-dev-server versions 5.2.5 and earlier terminate the whole Node.js process when an unauthenticated peer sends 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 value causes an uncaught exception in the host-validation path and crashes the dev server. Impact is limited to availability of the development server, no data disclosure, no code execution. Patches: upgrade to webpack-dev-server 5.2.6. Workarounds: keep the dev server bound to localhost (the default) and do not expose it to untrusted networks.
References
https://cna.openjsf.org/security-advisories.html
https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-m28w-2pqf-7qgj
Weaknesses
ce714d77-add3-4f53-aff5-83d477b104bb
CVSS impact metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.3 · Medium
Information
Source identifier
ce714d77-add3-4f53-aff5-83d477b104bb
Vulnerability status
Analyzed
Published
2026-07-03T18:16:24.687Z
3 months agoLast modified
2026-07-07T15:08:59.667Z
3 months ago