CVE-2026-14631

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.

CVSS Vector

References

• https://cna.openjsf.org/security-advisories.html
• https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-m28w-2pqf-7qgj