Update the WordPress wpForo Forum plugin to the latest available version (at least 2.0.6).
Ananda Dhakal discovered and reported this Insecure Direct Object References (IDOR) vulnerability in WordPress wpForo Forum Plugin. An insecure direct object reference vulnerability could allow a malicious actor to bypass authorization, authentication, access sensitive files/folders or interact with the database. This vulnerability has been fixed in version 2.0.6.