Popup Builder < 4.2.0 - Admin+ Stored Cross-Site Scripting

Description The plugin does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup). Note: The vendor was made aware of the issue on June 14 and 28, 2023

PoC

1. Click on “Add New”, and select the image popup. 2. Navigate to “Settings” and enable the “Floating Button” option. 3. Enter the XSS payload in the Text field: [Click Here](<javascript:alert\(document.cookie\)>) 4. Clicking on the button will get the popup. This XSS payload works on WordPress Admin.