A Cross-Site Scripting vulnerability was found in the WP Canvas - Shortcodes WordPress Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf. This issue can be exploited by authenticated users with the Contributor or higher role.
For feedback or questions about this advisory mail us at sumofpwn at securify.nl
This issue has been found during the Summer of Pwnage hacker event, running from July 1-29. A community summer event in which a large group of security bughunters (worldwide) collaborate in a month of security research on Open Source Software (WordPress this time). For fun. The event is hosted by Securify in Amsterdam.
OVE-20160724-0031
This issue was successfully tested on WP Canvas - Shortcodes WordPress Plugin version 1.92.
This issue has been addressed in WP Canvas - Shortcodes WordPress Plugin version 2.07.
The WP Canvas - Shortcodes WordPress Plugin provides a number of shortcodes that can be used in a WordPress post or page. A Cross-Site Scripting vulnerability was found in the WP Canvas - Shortcodes WordPress Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf. This issue can be exploited by authenticated users with the Contributor or higher role.
This issue exists due to the lack of validation on the url attributed of the wc_button shortcode. A Contributor or higher can create a button with a specially crafted Javascript payload. When a (logged) on user clicks on this button, the payload will be executed. This bypasses the unfiltered_html privilege of WordPress, which is normally only assigned to Editors & Administrators.
[wc_button type="primary" url="javascript:alert(1)" title="Visit Site" target="self" position="float"]Sample Content[/wc_button]
