CVE-2026-6402 - Medium Severity Vulnerability
Vulnerable Library - webpack-dev-server-3.10.3.tgz
Serves a webpack app. Updates the browser on changes.
Library home page: https://registry.npmjs.org/webpack-dev-server/-/webpack-dev-server-3.10.3.tgz
Path to dependency file: /client/package.json
Path to vulnerable library: /client/node_modules/webpack-dev-server/package.json
Dependency Hierarchy:
- react-scripts-3.4.1.tgz (Root Library)
- ❌ webpack-dev-server-3.10.3.tgz (Vulnerable Library)
Found in HEAD commit: 82d6429ed19093dbc56c092123fe7358b66c67b7
Found in base branch: master
Vulnerability Details
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.
Publish Date: 2026-05-12
URL: CVE-2026-6402
CVSS 3 Score Details (5.3)
Base Score Metrics:
- Exploitability Metrics:
- Attack Vector: Network
- Attack Complexity: High
- Privileges Required: None
- User Interaction: Required
- Scope: Unchanged
- Impact Metrics:
- Confidentiality Impact: High
- Integrity Impact: None
- Availability Impact: None
For more information on CVSS3 Scores, click here.
Suggested Fix
Type: Upgrade version
Origin: GHSA-79cf-xcqc-c78w
Release Date: 2026-05-12
Fix Resolution: webpack-dev-server - 5.2.4,https://github.com/webpack/webpack-dev-server.git - v5.2.4
Step up your Open Source Security Game with Mend here
CVE-2026-6402 - Medium Severity Vulnerability
Serves a webpack app. Updates the browser on changes.
Library home page: https://registry.npmjs.org/webpack-dev-server/-/webpack-dev-server-3.10.3.tgz
Path to dependency file: /client/package.json
Path to vulnerable library: /client/node_modules/webpack-dev-server/package.json
Dependency Hierarchy:
Found in HEAD commit: 82d6429ed19093dbc56c092123fe7358b66c67b7
Found in base branch: master
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.
Publish Date: 2026-05-12
URL: CVE-2026-6402
Base Score Metrics:
- Exploitability Metrics:
- Attack Vector: Network
- Attack Complexity: High
- Privileges Required: None
- User Interaction: Required
- Scope: Unchanged
- Impact Metrics:
- Confidentiality Impact: High
- Integrity Impact: None
- Availability Impact: None
For more information on CVSS3 Scores, click here.Type: Upgrade version
Origin: GHSA-79cf-xcqc-c78w
Release Date: 2026-05-12
Fix Resolution: webpack-dev-server - 5.2.4,https://github.com/webpack/webpack-dev-server.git - v5.2.4
Step up your Open Source Security Game with Mend here