webpack-dev-server up to 5.2.3 routine

Summaryinfo

A vulnerability was found in webpack-dev-server up to 5.2.3. It has been declared as problematic. This vulnerability affects unknown code. The manipulation results in routine. This vulnerability is known as CVE-2026-6402. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in webpack-dev-server up to 5.2.3. Affected is some unknown processing. The manipulation with an unknown input leads to a routine vulnerability. CWE is classifying the issue as CWE-749. The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted. This is going to have an impact on confidentiality. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-6402 since 04/15/2026. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 315211 (Linux Distros Unpatched Vulnerability : CVE-2026-6402), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.2.4 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (315211) and EUVD (EUVD-2026-29404). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• webpack-dev-server

Version

• 5.2.0
• 5.2.1
• 5.2.2
• 5.2.3

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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