Software Engineering Institute

Husdawg, LLC. provides an ActiveX control and signed Java Applet that are used for benchmarking the capabilities of a PC. The ActiveX control is provided by sysreqlab.dll, sysreqlabsli.dll, or sysreqlab2.dll, and the Java version is provided by SRLApplet.class, which may be contained in sysreqlab2.jar or sysreqlab.jar. The software is commonly used to determine if a system meets the requirements necessary to run video games. The System Requirements Lab components can be scripted to request an executable file from that server, which is then immediately executed. This file may be retrieved over HTTP, HTTPS, or FTP protocols.

A remote, unauthenticated attacker may be able to execute arbitrary code on a vulnerable server.

Apply an update

This vulnerability is addressed in version 3 of the System Requirements Lab software. This version is available on the systemrequirementlab.com web server. This version of the ActiveX control restricts which domains can call the methods provided by the control.

The primary ActiveX version of the software has also been disabled in Internet Explorer with the update for Microsoft Security Advisory (956391). Note that this update does not prevent the vulnerable Java version of the control from being used, nor does it disable every vulnerable version of the ActiveX control. Please see the CERT/CC Vulnerability Analysis Blog for more details about vulnerable Java applets.

Block outbound requests from the System Requirements Lab software

It may be possible to prevent this vulnerability from being exploited by filtering network requests from the System Requirements Lab software. Updates that occur using HTTP will contain the HTTP header:
User-Agent: SRL
When the System Requirements Lab software retrieves an update using the FTP protocol, it will use the following pattern:
USER anonymous
PASS IEUser@
SIZE //system.xml
RETR //system.xml
CWD //system.xml
Disable the System Requirements Lab ActiveX controls in Internet Explorer

The vulnerable ActiveX controls can be disabled in Internet Explorer by setting the kill bit for the following CLSIDs:

{67A5F8DC-1A4B-4D66-9F24-A704AD929EEE}
{BE833F39-1E0C-468C-BA70-25AAEE55775E}
{BE833F39-1E0C-468C-BA70-25AAEE55775F}
More information about how to set the kill bit is available in Microsoft Support Document 240797. Alternatively, the following text can be saved as a .REG file and imported to set the kill bit for these controls:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{67A5F8DC-1A4B-4D66-9F24-A704AD929EEE}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{BE833F39-1E0C-468C-BA70-25AAEE55775E}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{BE833F39-1E0C-468C-BA70-25AAEE55775F}]
"Compatibility Flags"=dword:00000400

Disable ActiveX

Disabling ActiveX controls in the Internet Zone (or any zone used by an attacker) appears to prevent exploitation of this and other ActiveX vulnerabilities. Instructions for disabling ActiveX in the Internet Zone can be found in the "Securing Your Web Browser" document. 

Disable Java

This vulnerability can be mitigated by disabling Java in your web browser. Instructions for disabling Java can be found in the "Securing Your Web Browser" document.