Bug 2560220 (CVE-2026-115895)

Summary:	CVE-2026-115895 happy-dom: happy-dom: Arbitrary code execution via unvalidated ECMAScript Module import alias
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	doconnor, dschmidt, jlanda, kshier, rbobbitt, simaishi, stcannon, yguenane
Target Milestone:	---	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in happy-dom. This vulnerability allows an attacker to achieve arbitrary code execution within the host Node.js environment. When JavaScript evaluation is enabled, the module compiler fails to validate named ECMAScript Module (ESM) import aliases before inserting them into generated code. A remote attacker could exploit this by supplying crafted HTML or module content containing a malicious alias to execute unauthorized code on the host system.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
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Description OSIDB Bzimport 2026-10-23 21:41:19 UTC

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.