XSS in Craftcms Cms

CVE-2026-55790

Craft CMS is a content management system (CMS). In versions 5.0.0-RC1 through 5.9.22 and 4.0.0-RC1 through 4.17.15, an attacker with only a GitHub account can plant a JavaScript payload in a craftcms/cms issue title. When a Craft admin uses the CraftSupport widget’s "Give feedback" screen and types a search term that returns the poisoned issue, the payload executes in the admin’s control panel session. No control panel account or elevated privileges are required on the attacker’s side. This issue has been fixed in versions 4.17.16 and 5.9.23.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (23.4th percentile) — read the EPSS interpretation.

Affected products

  • Craftcms Cms — versions >= 5.0.0-RC1, < 5.9.23, >= 4.0.0-RC1, < 4.17.16

Weakness classification (CWE)

References