CVE-2026-14631
The malformed value causes an uncaught exception in the host-validation path and crashes the dev server.
Does this matter?
Lower severity and a low EPSS score (0.52%). Track it; it rarely justifies an emergency change on its own.
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 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.52% probability · 42th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-20, CWE-248
- Affected
- webpack.js/webpack-dev-server
- Source
- ce714d77-add3-4f53-aff5-83d477b104bb
References
- https://cna.openjsf.org/security-advisories.htmlThird Party Advisory
- https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-m28w-2pqf-7qgjMitigation, Vendor Advisory, Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.