Sylius is an open source eCommerce platform. Prior to versions 1.9.10, 1.10.11, and 1.11.2, any other user can view the data if browser tab remains unclosed after log out. The issue is fixed in versions 1.9.10, 1.10.11, and 1.11.2. A workaround is available. The application must strictly redirect to login page even browser back button is pressed. Another possibility is to set more strict cache policies for restricted content.
CWE-200, CWE-668