App Store Pushing Out Corrupted App Downloads

Instapaper developer Marco Arment notes that Apple's App Store is apparently pushing out corrupted app binaries of a number of different applications to users. The issue, which renders the apps unusable, has apparently been triggered on app updates approved over the past few days.

Characterizations of this issue:

- The app crashes immediately on launch, every time, even after a delete and reinstall as long as the corrupt file is being served by the App Store.
- It doesn’t even show the Default.png before crashing. Just a split-second of a partial fade to black, then back to Springboard.
- It may only affect customers in some regions.
- If updating from iTunes, some customers might get a dialog citing error 8324 or 8326.
- Mac apps might show this dialog: “[App] is damaged and can’t be opened. Delete [App] and download it again from the App Store.”
- The console might show: AppleFairplayTextCrypterSession::fairplayOpen() failed, error -42110

Arment has collected a list of nearly two dozen apps that have been affected by the issue, and while Apple begin distributing a corrected version of Instapaper within a few hours yesterday, it remains unclear whether all affected apps have been fixed. For those who already downloaded corrupted versions of affected apps, the apps must be deleted and reinstalled.

GoodReader has more on the issue, including a description of how to back up settings and restore them upon reinstallation. GoodReader notes that the issue has appeared on both of its last two updates, speculating that something is going wrong with Apple's encryption process temporarily, and after a few hours the issue resolves itself.

While in theory Apple's servers must be ready to distribute the new app binary by the time they start sending update notifications to users' devices, something goes wrong inside Apple's distribution servers, and customers receive a damaged binary instead of the good one that we've sent to Apple. The exact reason is up to Apple to determine, but it looks like some binary encryption that happens internally in the App Store is only halfway-done at this point, and customers receive incorrectly (or partially?) encrypted binaries to their iPads. Those binaries do not get recognized by iOS as valid App Store executable binaries, and iOS simply refuses to launch them.

A few hours pass by, things settle down on Apple's servers, the update finally gets to places inside Apple's servers to which it was supposed to get, and everyone who downloads the update from that moment on, receives a correctly encrypted fully functional app binary.

Apple has yet to issue an official statement on the issue, and thus details remain unconfirmed for the time being, but developers are suggesting that users wait a few hours after receiving notifications about updated apps before updating their devices.

Update: Arment's list of apps confirmed to be affected by the issue has now grown to 70.