Winter: Authenticated backend users can bypass Users controller permission checks

Impact Affected versions of Winter CMS did not validate the handler name submitted through the form postback mechanism handler POST field in the same way as AJAX requests XWINTERREQUESTHANDLER header. The AJAX path validates that handler names match the onA-Z\w+ pattern, but the postback path...

PT-2026-76556

Name of the Vulnerable Software and Affected Versions Winter CMS versions prior to 1.2.13 Description An issue exists where the backend fails to validate the handler name submitted via the handler POST field during form postbacks. While AJAX requests are validated against the onA-Zw+ pattern, the...