HIGHCVE-2026-33943Published Modified CNA GitHub_M
CVE-2026-33943: Happy DOM ECMAScriptModuleCompiler: unsanitized export names are interpolated as executable code
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.
Metrics
- CVSS v3.1
- 8.8
- Severity
- HIGH
- Fixed in
- —
- Affected Products
- 1
Affected packages
- capricorn86 / happy-dom>= 15.10.0, < 20.8.8
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H