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.
History

Thu, 12 Mar 2026 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 12 Mar 2026 10:15:00 +0000

Type Values Removed Values Added
First Time appeared Craftcms
Craftcms craftcms
Vendors & Products Craftcms
Craftcms craftcms

Wed, 11 Mar 2026 18:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Craft has Reflective XSS via incomplete return URL sanitization
Weaknesses CWE-116
CWE-79
References
Metrics cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-03-11T17:37:19.065Z

Updated: 2026-03-12T14:00:23.631Z

Reserved: 2026-03-09T19:02:25.012Z

Link: CVE-2026-31859

cve-icon Vulnrichment

Updated: 2026-03-12T14:00:16.047Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-03-11T18:16:24.710

Modified: 2026-03-12T21:08:22.643

Link: CVE-2026-31859

cve-icon Redhat

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