The remote FTP server is prone to a cross-site request forgery attack.
The remote host is using ProFTPD, a free FTP server for Unix and Linux. The version of ProFTPD running on the remote host splits an overly long FTP command into a series of shorter ones and executes each in turn. If an attacker can trick a ProFTPD administrator into accessing a specially-formatted HTML link, he may be able to cause arbitrary FTP commands to be executed in the context of the affected application with the administrator's privileges.
Upgrade or patch according to vendor recommendations.