Microsoft has quietly stopped serving security updates to Internet Explorer 11 (IE11) on consumer and small business Windows 7 PCs unless the customer has successfully applied an April update for the browser.
The requirement and associated patch stoppage were similar to those Microsoft mandated for Windows 8.1 when it told customers they had to migrate to Windows 8.1 Update by June 10 or lose their patch privileges. The Windows 7 requirement, however, affected only IE11, Microsoft's newest browser, not the operating system.
Users who have not installed the IE security update issued on April 8 -- identified by Microsoft as MS14-018 -- on Windows 7, and who rely on Windows Update to download and install fixes, did not receive the June 10 IE update. Nor will IE11 receive any future updates, security or otherwise, until that MS14-018 has been installed. Windows Update will not display the appropriate IE11 patches.
Windows Update is used by consumers and some businesses, including most small companies, to keep their Windows PCs current with security patches.
"This update applies only to computers that are running Internet Explorer 11 and that do have update 2919355 (for Windows 8.1 or Windows Server 2012 R2) or update 2929437 (for Windows 7 SP1 or Windows Server 2008 R2 SP1) installed," stated the June support document associated with MS14-035, the massive June IE collection of 59 vulnerabilities, 47 of which applied to IE11. "All future security and non-security updates for Internet Explorer 11 require you to have update 2919355 or update 2929437 installed in order to receive updates (emphasis added)."
The cited ID numbers -- 2919355 and 2929437 -- refer to support documents linked to April 8's Windows 8.1 Update and the same day's IE security update for Windows 7, respectively.
Microsoft's support bulletins and other documents make for dense reading, but put in plain English, Microsoft is saying that unless IE11 on Windows 7 is upgraded with the April 8 update, it's lost patching privileges. The only way to regain access to IE11 patches is to download and install MS14-018.
The same rule will come into effect for enterprises and other large organizations on Aug. 12. Until then, IE11 on Windows 7 will be patched, even if the April upgrade has not been applied. Starting with fixes to IE11 issued in August, however, businesses using WSUS (Windows Server Update Services), Intune or System Center Configuration Manager will be cut off if they haven't upgraded IE11 using April's MS14-018.
If all this sounds familiar, it's because Microsoft has broadcast similar requirements for consumers and enterprises related to Windows 8.1. Any Windows 8.1 PC retrieving patches from Windows Update must have had Windows 8.1 Update installed to get June's security patches; businesses have until Aug. 12 to do the same.
Enterprises were given a three-month extension to the Windows 8.1-to-Windows 8.1 Update deadline after customers raised a stink about the five-week tempo Microsoft first demanded. The same extension has been given companies running IE11 on Windows 7.
Companies that have denied workers access to IE11 using a blocking toolkit released last October will not be affected. Nor will any Windows users running IE7, IE8, IE9 or IE10.
As far as Computerworld could determine, this is the first time that Microsoft selectively shut off patches to IE while still providing updates to the operating system.
It's unclear why Microsoft did this -- unlike the situation with Windows 8.1, the firm has not publicly explained the move or even publicized the requirement -- but it may be attributed to the significance of the IE11 update in April. In a support document, Microsoft listed numerous changes to IE11 on Windows 7.
Also possibly in play: Microsoft stressed that the reason why Windows 8.1 Update had to be applied was that the version was to be "the new servicing baseline" for the operating system. The company may consider the IE11 April update the same way, as a line in the sand that will serve as the assumption for all new fixes going forward.
Wes Miller, an analyst with Directions on Microsoft, agreed. "It does indeed sound like the same required baseline approach we saw with [Windows] 8.1 Update," Miller said in an email.
But the lack of information to Windows 7 users was unusual. Although the IE security bulletins released in April, May and June all mentioned the new requirements, those bulletins are rarely read by end users. In fact, they're designed for corporate IT staff. Even diligent readers could have easily missed the information in those bulletins. More glaring is that while Microsoft publicized the Windows 8.1-to-Windows 8.1 Update requirement in several April blogs, the company has not done the same for the IE11 on Windows 7 mandate.
Admittedly, most users who have Windows Update set to automatically download and install updates -- a majority of consumers -- do not need to be aware of such requirements, assuming those updates are successfully installed. But Windows and IE updates are not foolproof: They sometimes fail to take. In that case, users on Windows 7 running IE11 might not know that they are now unprotected, and will remain so until MS14-018 is deployed.
Businesses that have eschewed MS14-108 in order to test its impact on IE11 and how it interacts with their workflows or internal Web apps may also be unaware of their pending Aug. 12 deadline.
The oversight, if that is what it was, was the more remarkable for the widespread use of Windows 7 and IE11. According to Web metrics company Net Applications, Windows 7 powered 50% of all personal computers that went online in May, or 55% of all those running Windows.
Meanwhile, IE11 was the second-most popular version of Internet Explorer used in May, accounting for 29.3% of all instances of Microsoft's browser. Only IE8 was run by more people.
Much of IE11's popularity on Windows 7 stemmed from the automatic upgrades from IE10 that began late last year, after the browser was released for the 2009 operating system.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is gkeizer@computerworld.com.
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