Microsoft already on their way to patching FairUse4WM

Leave it to the Hawthorne Effect, right? It's been three days since we spilled the beans about the PlaysForSure-stripping FairUse4WM app, and already Microsoft's Windows Digital Media Division is issuing notices to its PlaysForSure licensees regarding patching up the problem. It's a little difficult for the likes of us to decode, but check it out for yourself, we've printed the letter in its entirety (sans email addresses) for your perusal. From what we can glean, Microsoft's prepared to combat this "new circumvention tool" by patching the individualized blackbox component (IBX) in PlaysForSure either as a push down through the software, or as an update available in the near future to Windows users. We won't butcher the technical nuances of this one any further though, so we'll let you guys see what's what and figure out how to keep everyone in the Fair Use fair use loop. Either way, guess it looks like Microsoft wasn't listening to our pleas; are you there Bill? It's us, Engadget.

---copied from source---
From: Windows Media License Agreements [email removed]
Sent: Monday, August 28, 2006 8:52 PM
To: Windows Media License Agreements
Subject: Update to the Windows Media Format SDK version 9.5 [identifier removed]

Dear Windows Media Licensee,

On August 25th, 2006, reported on a software tool that would allow consumers to decrypt WMDRM protected content. In response, on August 28, 2006, Microsoft released an update to the individualized blackbox component (IBX) designed to ensure that client applications using the Windows Media Format SDK version 9.5 who individualize to this latest version are robust against a new circumvention tool.

This update is not yet available for the Windows Media Format 9 Series FSDK or for users of Windows XP Media Center Edition 2005 Update Rollup 2.

Consumers are not at risk in any way. Content services can require that the updates be present in order to issue licenses by following the instructions below. Please note that the version number of IBX was not incremented as part of these updates to avoid delaying the release of these critical breach mitigations. Consequently, the only way to determine if the update is installed is to query the build number of the IBX. This requires code executing on the client.

To determine the build number of the IBX:

1. Ensure the PC is running the August 2005 update to Windows Media DRM. See the attached white paper for details.
2. Determine the path of the WMDRM folder. The path is stored in the registry at HKEY_LOCAL_MACHINE\Software\Microsoft\DRM\DataPath
3. Identify the file name of the latest IBX. If the machine has been individualized only once, the IBX file name will be indivbox.key. Otherwise, the IBX file name is in the form indivbox_xxx.key, where xxx are digits 0-9. The file name with the greatest value of xxx will be the latest IBX.
4. Call GetFileVersionInfo() to retrieve the build version of the file identified in step 3. See [link].
5. If the IBX file version is 11.0.5497.6285 or greater, then the updated IBX is installed

Please submit questions to [email removed]

Best regards,

Windows Media Licensing Department
Microsoft Windows Digital Media Division