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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.
https://github.com/capricorn86/happy-dom/commit/68324c21d7b98f53f7bb5a7b3e185bda7106e751 GitHub, Inc.
https://github.com/capricorn86/happy-dom/pull/2117 GitHub, Inc.
https://github.com/capricorn86/happy-dom/releases/tag/v20.8.9 GitHub, Inc.
https://github.com/capricorn86/happy-dom/security/advisories/GHSA-w4gp-fjgq-3q4g GitHub, Inc.

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.  

Change History

1 change records found show changes

Quick Info

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