Vulnerability Description
webpack-dev-server allows users to use webpack with a development server that provides live reloading. Prior to version 5.2.1, webpack-dev-server users' source code may be stolen when they access a malicious web site. Because the request for classic script by a script tag is not subject to same origin policy, an attacker can inject a malicious script in their site and run the script. Note that the attacker has to know the port and the output entrypoint script path. Combined with prototype pollution, the attacker can get a reference to the webpack runtime variables. By using `Function::toString` against the values in `__webpack_modules__`, the attacker can get the source code. Version 5.2.1 contains a patch for the issue.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Webpack.Js | Webpack-Dev-Server | < 5.2.1 |
Related Weaknesses (CWE)
References
- https://github.com/webpack/webpack-dev-server/commit/d2575ad8dfed9207ed810b5ea0cPatch
- https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-4v9v-hfq4ExploitVendor Advisory
FAQ
What is CVE-2025-30359?
CVE-2025-30359 is a vulnerability with a CVSS score of 5.3 (MEDIUM). webpack-dev-server allows users to use webpack with a development server that provides live reloading. Prior to version 5.2.1, webpack-dev-server users' source code may be stolen when they access a ma...
How severe is CVE-2025-30359?
CVE-2025-30359 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-30359?
Check the references section above for vendor advisories and patch information. Affected products include: Webpack.Js Webpack-Dev-Server.