On some devices, especially those that have undergone a SemiRestore, provisioning profiles are unable to be installed on the device. This is especially noticeable when users attempt to use the TestFlight app and find that they cannot install any app due to a vague "TestFlight is currently unavailable" error message.
Installing this package repairs the filesystem permissions for the provisioning profile directory and will restore functionality of TestFlight and well... installing provisioning profiles in general.
In other words, all SemiRestored devices have broken provisioning profile permissions, and should install this package. And yes, I've reported this bug to CoolStar and he is aware of it.