The WPScan security research team identified an Unauthenticated Reflected Cross-Site Scripting (XSS) vulnerability within the Zebra_Form PHP library, which is used by multiple WordPress plugins.
While investigating a dubious advisory related to a Cross-Site Scripting (XSS) vulnerability in the wp-ticket plugin, the Zebra_Form library was found to be responsible for the issue. At the time of writing, despite contacting the vendor multiple times, the latest version of Zebra_Form, version 2.9.8, is still affected.
Fortunately, the affected WordPress plugins were no longer maintained, or had a small number of active installations. Nevertheless, we wanted to make the public aware of the vulnerability affecting Zebra_Form in case it is used elsewhere.