As a reminder for context, Apple already did do a server side check for iCloud photos [1]. I think that's missing from the debate, what's changing is moving the

As a reminder for context, Apple already did do a server side check for iCloud photos [1]. I think that's missing from the debate, what's changing is moving the check to on device which many object to (and I and others have written enough about that). To add to this though : I think they built an extremely complex - and hopefully perfectly robust - system to make the check on device. On top of the other issues, it's massively important said process is not exploitable. The content of the NCMEC database is not public, one can argue for good reason, and if that effort to move on device lead to the database being leaked (and thus bad actors being able to "mark" content that they shouldn't share), that would be incredibly counter productive. Maybe only knowing that the database was updated is too much information to leak about this ? I think that's an additional concern to the ones already expressed many times, and I sincerly wish Apple had kept the checks server side even more now, as I only see downside to not doing so. [1] : https://nakedsecurity.sophos.com/2020/01/09/apples-scanning-icloud-photos-for-child-abuse-images/ https://nakedsecurity.sophos.com/2020/01/09/apples-scanning-...