wpDiscuz before 7.6.47 contains an unauthenticated denial of service vulnerability that allows anonymous users to trigger mass notification emails by exploiting the checkNotificationType() function. Attackers can repeatedly call the wpdiscuz-ajax.php endpoint with arbitrary postId and comment_id parameters to flood subscribers with notifications, as the handler lacks nonce verification, authentication checks, and rate limiting.
CWE-862, CWE-770, CWE-862