Zero Knowledge Backups with Android 9 and Titan Chip

Not zero-knowledge, but end-to-end with implied trust to the Titan chip.

If you are high-value target and NSA asked Google to have your backup on some kind of Titan simulation, they would have unlimited tries for guessing your PIN.

As I understand you don’t have any way to verify that your backup is actually encrypted using the Titan and that it doesn’t have bypass mode.