CVE-2026-34226

7.5 HIGH
Published: March 27, 2026 Modified: April 01, 2026
View on NVD

Description

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Versions prior to 20.8.9 may attach cookies from the current page origin (`window.location`) instead of the request target URL when `fetch(..., { credentials: "include" })` is used. This can leak cookies from origin A to destination B. Version 20.8.9 fixes the issue.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/capricorn86/happy-dom/blob/f8d8cad41e9722fab9eefb9dfb3cca696462e908/packages/happy-dom/src/fetch/utilities/FetchRequestHeaderUtility.ts
Source: security-advisories@github.com
Patch
https://github.com/capricorn86/happy-dom/commit/68324c21d7b98f53f7bb5a7b3e185bda7106e751
Source: security-advisories@github.com
Patch
https://github.com/capricorn86/happy-dom/pull/2117
Source: security-advisories@github.com
Issue Tracking Patch
https://github.com/capricorn86/happy-dom/releases/tag/v20.8.9
Source: security-advisories@github.com
Product Release Notes
https://github.com/capricorn86/happy-dom/security/advisories/GHSA-w4gp-fjgq-3q4g
Source: security-advisories@github.com
Exploit Vendor Advisory

5 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
0.0%
10th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-201 CWE-359

Affected Vendors

capricorn86

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