BuddyPress is an open source WordPress plugin to build a community site. In releases of BuddyPress from 5.0.0 before 7.2.1 it's possible for a non-privileged, regular user to obtain administrator rights by exploiting an issue in the REST API members endpoint. The vulnerability has been fixed in BuddyPress 7.2.1. Existing installations of the plugin should be updated to this version to mitigate the issue.
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.