Description

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. In versions 15.10.0 through 20.8.7, a code injection vulnerability in `ECMAScriptModuleCompiler` allows an attacker to achieve Remote Code Execution (RCE) by injecting arbitrary JavaScript expressions inside `export { }` declarations in ES module scripts processed by happy-dom. The compiler directly interpolates unsanitized content into generated code as an executable expression, and the quote filter does not strip backticks, allowing template literal-based payloads to bypass sanitization. Version 20.8.8 fixes the issue.

INFO

Published Date :

2026-03-27T21:15:19.186Z

Last Modified :

2026-03-27T21:58:16.284Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-33943 vulnerability.

Vendors Products
Capricorn86
  • Happy-dom
  • Happy Dom
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-33943.

URL Resource
https://github.com/capricorn86/happy-dom/commit/5437fdf8f13adb9590f9f52616d9f69c3ee8db3c cve-icon cve-icon cve-icon
https://github.com/capricorn86/happy-dom/releases/tag/v20.8.8 cve-icon cve-icon cve-icon
https://github.com/capricorn86/happy-dom/security/advisories/GHSA-6q6h-j7hj-3r64 cve-icon cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-33943 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-33943 cve-icon
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CVSS Vulnerability Scoring System

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