Torrentpier version 2.4.1 allows executing arbitrary commands on the server. This is possible because the application is vulnerable to insecure deserialization.

TorrentPier is an open source BitTorrent Public/Private tracker engine, written in php. In versions up to and including 2.8.8, an authenticated SQL injection vulnerability exists in the moderator control panel (`modcp.php`). Users with moderator permissions can exploit this vulnerability by supplying a malicious `topic_id` (`t`) parameter. This allows an authenticated moderator to execute arbitrary SQL queries, leading to the potential disclosure, modification, or deletion of any data in the database. Although it requires moderator privileges, it is still severe. A malicious or compromised moderator account can leverage this vulnerability to read, modify, or delete data. A patch is available at commit 6a0f6499d89fa5d6e2afa8ee53802a1ad11ece80.