CVE-2026-34226
Happy DOM's fetch credentials include uses page-origin cookies instead of target-origin cookies
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
9th
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.
| CWE | CWE-201 CWE-359 |
| Vendor | capricorn86 |
| Product | happy-dom |
| Published | Mar 27, 2026 |
| Last Updated | Mar 31, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
capricorn86 / happy-dom
< 20.8.9
References
github.com: https://github.com/capricorn86/happy-dom/security/advisories/GHSA-w4gp-fjgq-3q4g github.com: https://github.com/capricorn86/happy-dom/pull/2117 github.com: https://github.com/capricorn86/happy-dom/commit/68324c21d7b98f53f7bb5a7b3e185bda7106e751 github.com: https://github.com/capricorn86/happy-dom/blob/f8d8cad41e9722fab9eefb9dfb3cca696462e908/packages/happy-dom/src/fetch/utilities/FetchRequestHeaderUtility.ts github.com: https://github.com/capricorn86/happy-dom/releases/tag/v20.8.9