A AegiFlow
MEDIUMCVSS 6.5EPSS 0.3%

CVE-2026-118661

CVE-2026-118661 updated by NVD

Published
2026-10-28
Modified
2026-11-05
EPSS percentile
20%
Sources
github-advisory, nvd

Summary

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 20.14.6, Happy DOM's CookieContainer in src/cookie/CookieContainer.ts does not correctly validate or match Domain cookie attributes. It can accept a Domain unrelated to the origin setting the cookie, including a public suffix, and separately treats an unrelated suffix-sharing hostname as a match because cookieMatchesURL does not enforce a DNS-label boundary. In server-side rendering and prerendering applications that contact attacker-controlled origins and then make requests to a victim origin, these behaviors can plant and deliver a forged cookie, enabling cookie injection or session fixation. This issue is fixed in version 20.14.6.

Affected packages

EcosystemPackageAffected versionsFixed versions
npmhappy-dom—20.14.6

Remediation: Upgrade to 20.14.6 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

CVE® is a registered trademark of The MITRE Corporation. CVE content reproduced under the CVE Terms of Use; copyright designation © MITRE.

EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.