Apple made an awful lot of its software free this week, including its latest OS X update, iWork and iLife.
But according to a bug spotted by 9to5Mac, it may have inadvertently made a bunch more software free too - and open to abuse by hackers.
It seems that any user who had previously downloaded a trial or illegally downloaded version of iWork, iLife or the premium photo software Aperture is now being moved to legal, downloaded copies.
It means that much of Apple's software, including the £54.99 Aperture, can be downloaded for free, relatively straightforwardly.
Many users report being inadvertently upgraded automatically, as the Mac App Store handles which software is ready to be updated for you.
9to5Mac supposes that the issue stems from the App Store being unable to check whether an app has been activated legally before downloading the new version.
Meanwhile Apple has pulled the trial versions of its software from its website - apparently in recognition of the bug.
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