CVE-2026-118660

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.0, Happy DOM loads iframe src URLs and link rel="stylesheet" href URLs by default while parsing untrusted HTML on the server because disableIframePageLoading and disableCSSFileLoading default to false. An attacker who controls parsed HTML can therefore cause server-side requests to arbitrary internal or cloud endpoints without an application opt-in and may expose confidential responses or credentials returned by those endpoints. This issue is fixed in version 21.0.0.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/capricorn86/happy-dom/commit/0a99c7525a1d0043e3182843ae33466ab7b19e74
https://github.com/capricorn86/happy-dom/pull/2502
https://github.com/capricorn86/happy-dom/releases/tag/v21.0.0
https://github.com/capricorn86/happy-dom/security/advisories/GHSA-c8p4-j97h-3vg8

Configurations

No configuration.

History

28 Oct 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-28 21:16

Updated : 2026-10-29 18:17

NVD link : CVE-2026-118660

Mitre link : CVE-2026-118660

CVE.ORG link : CVE-2026-118660

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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