Windows users have received a patch meant to fix a potentially serious security loophole in PowerPoint. However, Microsoft has earned criticism for not simultaneously issuing a patch for the Mac edition.

Microsoft has been aware of the problem for weeks. The issue could let hackers trick users into opening an infected PowerPoint file, and would then be able to take control of a system.

Microsoft figured out a solution for Windows, but hasn't yet done so for the Mac edition. This left the firm in an unenviable dilemma about whether to wait until it had a Mac patch ready or issue the Windows patch as soon as it was successfully tested.

Patch Tuesday Solution

The company decided to publish the Windows update at the earliest opportunity, which was Tuesday this week. Its explanation was that "given this situation of a package available for an entire product line that protects the vast majority of customers at risk within the predictable release cycle, we made a decision to go early with the Windows packages." (Source: technet.com)

That's not gone over well with the Mac community, with critics saying that issuing the Windows patch alerted hackers to the fact that the problem exists, leaving Mac users particularly vulnerable to attacks.

Mac Attack Purely Theoretical

Microsoft claims all known attacks so far have been on Windows machines and at the moment the Mac vulnerability is purely theoretical. It also says that, contrary to some statements, the Windows update does not contain details which would help hackers do a better job of exploiting the problem on Macs.

Double Standards Claim

Security researchers are accusing Microsoft of hypocrisy. They say the firm regularly demands that anyone who discovers a security problem with Microsoft products keep it secret until a patch has been developed, a policy known as 'responsible disclosure' -- and a policy Microsoft appears to be breaching with the news of the PowerPoint Mac flaw. (Source: computerworld.com)

Anyone using PowerPoint on Windows should make sure to apply the update immediately if they don't already use the Automatic Updates feature in Windows.

Until there's a Mac patch, users on that system should take extra care not to open any PowerPoint files that they have received unexpectedly unless they've contacted the sender and confirmed they are legitimate.