CVE-2026-115895

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. From 17.0.0 until 21.0.4, packages/happy-dom/src/module/ECMAScriptModuleCompiler.ts accepts a named ESM import alias without validating that it is a JavaScript binding identifier before inserting it into a generated destructuring binding. With enableJavaScriptEvaluation enabled, attacker-controlled HTML or module source can use an invalid alias that becomes a valid default initializer after compilation, causing the generated JavaScript to execute in the Node.js host process. The demonstrated reachable path uses a JSON module import attribute, which prevents the malicious alias from being emitted again in a later ESM circular-import assignment and keeps the generated function syntactically valid. This incomplete fix for CVE-2026-33943 is a distinct residual path because the earlier remediation validated the local export importName path but not the named-import alias. This issue is fixed in version 21.0.4.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/capricorn86/happy-dom/commit/fd163520b74d9fa146be91f7b4e4f46d6cccbe13
https://github.com/capricorn86/happy-dom/pull/2537
https://github.com/capricorn86/happy-dom/releases/tag/v21.0.4
https://github.com/capricorn86/happy-dom/security/advisories/GHSA-834v-8h66-3h79
https://github.com/capricorn86/happy-dom/security/advisories/GHSA-834v-8h66-3h79

Configurations

No configuration.

History

30 Oct 2026, 19:18

Type	Values Removed	Values Added
References	~~() https://github.com/capricorn86/happy-dom/security/advisories/GHSA-834v-8h66-3h79 -~~	() https://github.com/capricorn86/happy-dom/security/advisories/GHSA-834v-8h66-3h79 -

23 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-23 22:16

Updated : 2026-10-30 19:18

NVD link : CVE-2026-115895

Mitre link : CVE-2026-115895

CVE.ORG link : CVE-2026-115895

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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