CVE-2026-34226CWE-201CWE-359

CVE-2026-34226

High · published March 28, 2026

CVSS v3.1
7.5
EPSS
1%
Percentile
47.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00589 · 47.4th percentile
Weaknesses
CWE-201 · Insertion of Sensitive Information Into Sent Data; CWE-359 · Exposure of Private Personal Information to an Unauthorized Actor
Published
2026-03-28T02:16Z
Affected products (1)
ProductVersionsFixed in
capricorn86/happy_dom< 20.8.920.8.9
References (8)
https://github.com/capricorn86/happy-dom/blob/f8d8cad41e9722fab9eefb9dfb3cca696462e908/packages/happy-dom/src/fetch/utilities/FetchRequestHeaderUtility.ts · [email protected]https://github.com/capricorn86/happy-dom/commit/68324c21d7b98f53f7bb5a7b3e185bda7106e751 · [email protected]https://github.com/capricorn86/happy-dom/pull/2117 · [email protected]https://github.com/capricorn86/happy-dom/releases/tag/v20.8.9 · [email protected]https://github.com/capricorn86/happy-dom/security/advisories/GHSA-w4gp-fjgq-3q4g · [email protected]https://access.redhat.com/security/cve/CVE-2026-34226 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://bugzilla.redhat.com/show_bug.cgi?id=2452519 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34226.json · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
EPSS history
Timeline
  • 27 MAR 21:17Z
    Happy DOM's fetch credentials include uses page-origin cookies instead of target-origin cookies
    cvelistv5