
Not only does iOS 8.3 patch another exploit used by the TaiG jailbreak, but Apple appears to have added yet another measure of security in the newly-released firmware update related to using third-party file browsers for modifying the file contents of applications via a USB connection... so now they don't work anymore.
Applications of this nature include, but are not limited to, iExplorer, iFunBox, PhoneView, and iTools. They are available for both Mac and Windows users and have been widely used by users to modify or transfer files from applications on the device to a computer without having to use iTunes.
Above, you can see a screenshot of iFunBox failing to connect to open a directory to a restricted application in iOS 8.3. The warning says that users now need to be jailbroken to use the software with specific applications due to a security patch by Apple that no longer permits the software to access many the device's internal files.
While Apple sees this as increased security for their devices, those that used the software to modify files and make changes to their devices will be disappointed by the change.
The developers of the applications in question report that they're working on workarounds, and have publicly announced that the issue is directly related to iOS 8.3:
Sources: MacRumors
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