CVE-2026-6402 (GCVE-0-2026-6402)

Vulnerability from cvelistv5 – Published: 2026-05-12 07:45 – Updated: 2026-05-12 13:00
VLAI
Title
webpack-dev-server vulnerable to cross-origin source code exposure on non-HTTPS origins
Summary
webpack-dev-server versions up to and including 5.2.3 are vulnerable to cross-origin source code exposure when serving over a non-potentially trustworthy origin such as plain HTTP. The previous fix relied on the Sec-Fetch-Mode and Sec-Fetch-Site request headers, which browsers omit for non-trustworthy origins, allowing a malicious site to load the bundled source as a script and read it across origins. Impact: an attacker controlling a website visited by a developer running webpack-dev-server can recover the application source code when the dev server runs over HTTP at a guessable host and port. Chromium based browsers from Chrome 142 onward are not affected due to local network access restrictions. Upgrade to webpack-dev-server 5.2.4 or later, which sets Cross-Origin-Resource-Policy: same-origin on responses.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-12 12:57 UTC
CWE
  • CWE-749 - Exposed Dangerous Method or Function
Assigner
openjs CNA under the redhat root
CNA scorecard C 65/100 over 118 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
webpack-dev-server webpack-dev-server Affected: 0 , < 5.2.4 (semver)
Unaffected: 5.2.4 (semver)
guessed Create a notification for this product.
Credits
sapphi-red Ulises Gascón Sebastian Beltran Alexander Akait
Show details on NVD website
To clipboard 

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