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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-34226 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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

Weakness Enumeration

CWE-ID CWE Name Source
CWE-201 Insertion of Sensitive Information Into Sent Data GitHub, Inc.  
CWE-359 Exposure of Private Personal Information to an Unauthorized Actor GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-34226
NVD Published Date:
03/27/2026
NVD Last Modified:
04/01/2026
Source:
GitHub, Inc.