PSA: Apple can't run CSAM checks on devices with iCloud Photos turned offWhat you need to know
Apple's new on-device CSAM checks are only run on photos that are to be uploaded to iCloud Photos.
Photos aren't checked on devices with iCloud Photos disabled.
Apple also confirmed that it cannot check photos that are inside iCloud backups
Just a quick reminder.
Apple announced new on-device CSAM detection techniques yesterday and there has been a lot of confusion over what the feature can and cannot do. Contrary to what some people believe, Apple cannot check images when users have iCloud Photos disabled.
Apple's confirmation of the new CSAM change did attempt to make this clear, but perhaps didn't make as good a job of it as it could. With millions upon millions of iPhone users around the world, it's to be expected that some could be confused.
Using another technology called threshold secret sharing, the system ensures the contents of the safety vouchers cannot be interpreted by Apple unless the iCloud Photos account crosses a threshold of known CSA...
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PSA: Apple can't run CSAM checks on devices with iCloud Photos turned off
