CVE-2026-34226highCWE-201CWE-359

CVE-2026-34226: high-severity vulnerability in capricorn86 happy-dom

Happy DOM's fetch credentials include uses page-origin cookies instead of target-origin cookies

Published · Updated

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
capricorn86 · happy-dom
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