Are iCloud Photos end-to-end encrypted?

Only if you turn on Advanced Data Protection. By default iCloud Photos are encrypted in transit and on Apple's servers, but Apple holds the keys. With Advanced Data Protection on, Photos are end-to-end encrypted and the keys stay on your trusted devices. Apple says some Photos metadata is not covered, and Shared Albums are not covered at all.

Standard protection and Advanced Data Protection

Apple's iCloud data security overview separates two modes. With standard data protection, which is the default, iCloud data is encrypted in transit and at rest and Apple holds the keys. That is how Apple can help if you forget your password. A set of categories, including passwords in iCloud Keychain and Health data, is end-to-end encrypted even under the default.

With Advanced Data Protection, the number of end-to-end encrypted categories rises, and the list includes device backups stored in iCloud, Photos and Notes. Apple says your trusted devices then "retain sole access to the encryption keys for the majority of your iCloud data".

What stays outside it

  • Some Photos metadata, such as checksums, favorite, hidden and deleted flags and view counts, remains under standard protection.
  • Shared Albums, iWork collaboration and "anyone with the link" sharing do not support Advanced Data Protection.
  • iCloud Mail, Contacts and Calendars always use Apple-held keys.
  • Access to iCloud data on the web at iCloud.com is disabled while it is on.

The recovery trade-off

Because Apple does not hold the keys, losing access to your account has a harder recovery path. Before you can turn the setting on, Apple guides you to set up at least one recovery method: a recovery contact or a recovery key. Your device passcode or password is also a route. If you lose all of them, Apple cannot help you.

What you can do

  1. Decide whether you need the protection. If your concern is Apple or someone who gains access to Apple's servers reading your photos, this is the setting that matters.
  2. On an iPhone, go to Settings, your name, iCloud, Advanced Data Protection, then Turn on Advanced Data Protection. You need an Apple Account with two-factor authentication and a device passcode, and Managed Apple Accounts and child accounts are not eligible.
  3. Set up and test your recovery method before you rely on it.

What this does not cover

It does not make the Hidden album stronger against a person holding your unlocked phone. And it does not touch photos you have shared in a Shared Album.

QuestionAnswer
Encrypted in transit and at rest by default?Yes
Can Apple hold the keys by default?Yes
End-to-end encrypted by default?No
End-to-end encrypted with Advanced Data Protection?Yes, apart from the metadata Apple lists

Related: can Apple see your hidden photos, is the Hidden album secure, the short answer can Apple see my hidden photos, and Hidden album or vault app.

Frequently asked questions

Are iCloud Photos end-to-end encrypted by default?

No. They are encrypted, but Apple holds the keys unless you turn on Advanced Data Protection.

What is the downside of Advanced Data Protection?

Apple cannot recover that data for you, so you need a recovery contact, a recovery key or your device passcode. iCloud.com web access is disabled while it is on.

Are Shared Albums covered?

No. Apple says Shared Albums do not support Advanced Data Protection.

Is the hidden flag encrypted end to end?

Apple lists hidden and deleted flags among the metadata that stays under standard protection.

Sources

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