high7.5
CVE-2026-34226
Happy DOM is a JavaScript implementation of a web browser without its graphical user interface.
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | happy-dom | < 20.8.9 | 20.8.9 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Capricorn86 | Happy Dom | before 20.8.9 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/capricorn86/happy-dom/blob/f8d8cad41e9722fab9eefb9dfb3cca696462e908/packages/happy-dom/src/fetch/utilities/FetchRequestHeaderUtility.ts
- https://github.com/capricorn86/happy-dom/commit/68324c21d7b98f53f7bb5a7b3e185bda7106e751
- https://github.com/capricorn86/happy-dom/pull/2117
- https://github.com/capricorn86/happy-dom/releases/tag/v20.8.9
- https://github.com/capricorn86/happy-dom/security/advisories/GHSA-w4gp-fjgq-3q4g
- https://access.redhat.com/security/cve/CVE-2026-34226
- https://bugzilla.redhat.com/show_bug.cgi?id=2452519
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34226.json
- https://github.com/advisories/GHSA-w4gp-fjgq-3q4g
- https://nvd.nist.gov/vuln/detail/CVE-2026-34226