A choice cut from Microsoft's official response to the reported Black Screen of Death fiasco. Apparently, there are two possibilities here: a faulty security update is crippling PCs without warning; or, um, mass hysteria? (Im)possible!
To Microsoft's credit, it really isn't clear what exactly is going on here. PC World reports with confidence that the issue is related to changes that a November 10th security update makes to the Windows Access Control List. And security firm Prevx even has a fix. That all fits together. But!
Microsoft's update apparently doesn't touch Windows' aforementioned sensitive bits:
While these reports weren't brought to us directly, from our research into them, it appears they're saying that our security updates are making permission changes in the registry to the value for the HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell key.
We've conducted a comprehensive review of the November Security Updates, the Windows Malicious Software Removal Tool, and the non-security updates we released through Windows Update in November. That investigation has shown that none of these updates make any changes to the permissions in the registry. Thus, we don't believe the updates are related to the "black screen" behavior described in these reports.
They point to malware as a possible culprit, which would be fascinating: That would mean that an unluckily timed Windows Update was lumped in with a malware attack by merely happening in the same timeframe. Either way, the "Black Screen of Death" is too catchy to let die, no matter who ends up owning up to it.
UPDATE: Now even Prevx is letting Microsoft off the hook, which narrows the possibilities down to... everything else in the entire world except for that November 10th update. Microsoft was right:
Having narrowed down a specific trigger for this condition we've done quite a bit of testing and re-testing on the recent Windows patches including KB976098 and KB915597 as referred to in our previous blog. Since more specifically narrowing down the cause we have been able to exonerate these patches from being a contributory factor.
Malware? Mystery? Who knows. [Microsoft Technet]