Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in wpeverest User Registration user-registration allows Reflected XSS.This issue affects User Registration: from n/a through < 4.2.0.
The User Registration & Membership WordPress plugin before 4.1.3 does not properly validate data in an AJAX action when the Membership Addon is enabled, allowing attackers to authenticate as any user, including administrators, by simply using the target account's user ID.