CVE-2026-31859

Craft is a content management system (CMS). The fix for CVE-2025-35939 in craftcms/cms introduced a strip_tags() call in src/web/User.php to sanitize return URLs before they are stored in the session. However, strip_tags() only removes HTML tags (angle brackets) -- it does not inspect or filter URL schemes. Payloads like javascript:alert(document.cookie) contain no HTML tags and pass through strip_tags() completely unmodified, enabling reflected XSS when the return URL is rendered in an href attribute. This vulnerability is fixed in 5.9.7 and 4.17.3.

CVSS

No CVSS.

References

Link	Resource
https://github.com/craftcms/cms/security/advisories/GHSA-fvwq-45qv-xvhv

Configurations

No configuration.

History

11 Mar 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-11 18:16

Updated : 2026-03-12 21:08

NVD link : CVE-2026-31859

Mitre link : CVE-2026-31859

CVE.ORG link : CVE-2026-31859

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-116

Improper Encoding or Escaping of Output

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