tnftpd before 20080929 splits large command strings into multiple commands, which allows remote attackers to conduct cross-site request forgery (CSRF) attacks via unknown vectors, probably involving a crafted ftp:// link to a tnftpd server.
Cross-Site Request Forgery The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.