The User Registration WordPress plugin before 220.127.116.11 does not sanitize 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).
The User Registration plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 3.0.1 via deserialization of untrusted input from the 'profile-pic-url' parameter. This allows authenticated attackers, with subscriber-level permissions and above, to inject a PHP Object. No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.
The User Registration plugin for WordPress is vulnerable to arbitrary file uploads due to a hardcoded encryption key and missing file type validation on the 'ur_upload_profile_pic' function in versions up to, and including, 3.0.2. This makes it possible for authenticated attackers with subscriber-level capabilities or above to upload arbitrary files on the affected site's server which may make remote code execution possible. This was partially patched in version 3.0.2 and fully patched in version 18.104.22.168.
The User Registration WordPress plugin before 22.214.171.124 does not properly restrict the files to be uploaded via an AJAX action available to both unauthenticated and authenticated users, which could allow unauthenticated users to upload PHP files for example.
The User Registration WordPress plugin before 2.0.2 does not properly sanitise the user_registration_profile_pic_url value when submitted directly via the user_registration_update_profile_details AJAX action. This could allow any authenticated user, such as subscriber, to perform Stored Cross-Site attacks when their profile is viewed