An issue was discovered in phpFox before 4.8.14. The url request parameter passed to the /core/redirect route is not properly sanitized before being used in a call to the unserialize() PHP function. This can be exploited by remote, unauthenticated attackers to inject arbitrary PHP objects into the application scope, allowing them to perform a variety of attacks, such as executing arbitrary PHP code.
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.