CVE-2026-118660

HIGH
MEDIUM Priority: 0.03 BB Relevance: 77/100
Published: 2026-10-28 Modified: 2026-10-28 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction Conf. Impact Scope Change

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Changed
C: High
I: None
A: None

Description

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.

Weakness Classification (1)

Affected Software (2)

VendorProductVersion
capricorn86 happy-dom < 21.0.0
capricorn86 happy-dom < 21.0.0

Bug Bounty Relevance

77 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

8.6 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

EPSS — Exploitation Probability

0.40%
Raw Score 0.004050
Percentile 34.7%
Date 2026-10-29

Intelligence Sources

mitre ref →
nvd ref →