5.3
MEDIUM CVSS 3.1
CVE-2026-14631
webpack-dev-server vulnerable to denial of service via a malformed Host or Origin header
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.

INFO

Published Date :

July 3, 2026, 5:23 p.m.

Last Modified :

July 3, 2026, 5:23 p.m.

Remotely Exploit :

Yes !

Source :

openjs
Affected Products

The following products are affected by CVE-2026-14631 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM ce714d77-add3-4f53-aff5-83d477b104bb
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Upgrade webpack-dev-server to a patched version or restrict access.
  • Upgrade webpack-dev-server to version 5.2.6 or later.
  • Restrict dev server access to localhost.
  • Avoid exposing the dev server to untrusted networks.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-14631 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.