Apple has failed to warn its customers, but Trend Micro's Zero Day Initiative issued a call to action and last night the US-CERT team confirmed: If you have QuickTime on your Windows system, uninstall it now.
Many people picked up QuickTime when it was a required component of iTunes for Windows. That's no longer the case -- iTunes now works fine without QuickTime. While opinions on iTunes vary (I can hardly mention it without hyperventilating), there's no ambiguity about QuickTime. Uninstall it now.
Here's what Trend Micro says:
Apple is deprecating QuickTime for Microsoft Windows. They will no longer be issuing security updates for the product on the Windows Platform and recommend users uninstall it… Our Zero Day Initiative has just released two advisories ZDI-16-241 and ZDI-16-242 detailing two new, critical vulnerabilities affecting QuickTime for Windows. These advisories are being released in accordance with the Zero Day Initiative's Disclosure Policy for when a vendor does not issue a security patch for a disclosed vulnerability. And because Apple is no longer providing security updates for QuickTime on Windows, these vulnerabilities are never going to be patched. We're not aware of any active attacks against these vulnerabilities currently. But the only way to protect your Windows systems from potential attacks against these or other vulnerabilities in Apple QuickTime now is to uninstall it.
The US-CERT alert TA16-105A essentially repeats the Trend Micro/ZDI announcement, with no additional information.
I looked high and low on Apple's website and couldn't find any notification about QuickTime for Windows getting tossed to the dogs. All I could find is this lame uninstall primer, last modified more than a month ago, which at its heart points you to an old Microsoft page with generic instructions for uninstalling programs.
Microsoft's removal instructions (which include a -- gasp -- Silverlight video) work for Windows 7 and Vista: Start > Control Panel > Programs > Programs and Features, then double-click on QuickTime (or click once and click Uninstall). For Windows 8.1 or 10, right-click Start and choose Control Panel, then follow the Win7 instructions. There's a cooler interface in Win10: Start > Settings > System > Apps & features, then click on QuickTime and click Uninstall. They all work the same way.
I've seen published reports all over the Web that Apple is ending support for QuickTime for Windows. But I have yet to hear anything from the horse's mouth. It's hard to understand why Apple would keep that kind of pronouncement under wraps for months.