Winter: Stored XSS through Editor Settings custom styles

Impact Authenticated Backend Users with the backend.manageeditor "Manage editor settings" permission can provide custom styles through Settings → Editor Settings → Markup Styles that are compiled through the LESS CSS parser and rendered on every backend page. Previously, the compiled output was n...

Winter: Stored XSS through Brand Settings custom styles

Impact Users with the backend.managebranding "Customize the back-end" permission can provide custom CSS through Settings → Customize Backend → Styles that is compiled through the LESS CSS parser and rendered on every backend page. Previously, the compiled output was not sanitized, which could hav...

PT-2026-76553

Name of the Vulnerable Software and Affected Versions Winter versions 1.2.10 through 1.2.12 Description Authenticated backend users with the backend.manage editor permission can store custom Markup Styles via Settings → Editor Settings → Markup Styles. These styles are compiled by the LESS parser...

PT-2026-76552

Name of the Vulnerable Software and Affected Versions Winter versions prior to 1.2.13 Description Custom CSS provided through the Brand Settings Styles field is compiled by the LESS parser and rendered without sanitization on every backend page. This allows a user with the backend.manage branding...