static/ajax.php in PHPFox 3.7.3, 3.7.4, and 3.7.5 allows remote authenticated users to bypass intended "Only Me" restrictions and comment on a private publication via a request with a modified val[item_id] parameter for the publication.
https://exchange.xforce.ibmcloud.com/vulnerabilities/92336
http://www.securityfocus.com/bid/66677
http://www.securityfocus.com/archive/1/531745/100/0/threaded