CVE-2026-118660
Published:October 28, 2026
Updated:October 30, 2026
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.
Affected Packages
https://github.com/capricorn86/happy-dom.git (GITHUB):
Affected version(s) >=v20.0.0 <v21.0.0Fix Suggestion:
Update to version v21.0.0happy-dom (NPM):
Affected version(s) >=19.0.0 <21.0.0Fix Suggestion:
Update to version 21.0.0Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.2
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.6
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Server-Side Request Forgery
EPSS
Base Score:
0.40