CVE-2026-14631

Summary

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.

Affected Software

VendorProductVersion RangeStatus
webpack-dev-serverwebpack-dev-server0 < 5.2.6affected
webpack-dev-serverwebpack-dev-server5.2.6unaffected

Weaknesses

  • CWE-20: CWE-20: Improper Input Validation
  • CWE-248: CWE-248: Uncaught Exception

References