The vulnerability in Adenion Blog2Social plugin for WordPress (versions prior to 9.1.0) arises from insufficient authorization checks in the b2s_search_user AJAX handler located in includes/Ajax/Get.php. This handler calls B2S_Tools::searchUser() in includes/Tools.php, which returns email addresses of matching users without verifying that the caller has the list_users capability. Consequently, any user with the edit_posts capability can retrieve email addresses of all registered users, including administrators.

The exposure of email addresses to low-privileged users can lead to privacy violations and may facilitate targeted phishing or social engineering attacks against users, including administrators. The vulnerability does not allow privilege escalation or direct system compromise but leaks sensitive user information.

No official patch or vendor advisory is provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict the edit_posts capability to trusted users only and monitor for suspicious activity related to user enumeration.