The ProfileGrid WordPress plugin before 5.3.1 provides an AJAX endpoint for resetting a user password but does not implement proper authorization. This allows a user with low privileges, such as subscriber, to change the password of any account, including Administrator ones.
CWE-863 - Incorrect Authorization
Authorization is a security mechanism performed by an application to grant or deny access to the requested resources by verifying the privileges of the user. When an application lacks effective authorization mechanisms, it enables unauthorized users to gain unintended privileges and illegitimate access to resources. Such a vulnerability may result in exposure of sensitive information, denial of service, arbitrary code execution, and complete system takeover.