iCloud secures your data by encrypting it when it's sent over the Internet, storing it in an encrypted format when kept on server (review the table below for detail), and using secure tokens for authentication. This means that your data is protected from unauthorized access both while it is being transmitted to your devices and when it is stored in the cloud. iCloud uses a minimum of 128-bit AES encryption—the same level of security employed by major financial institutions—and never provides encryption keys to any third parties.
Security and iCloud features
The table below summarizes how your data is secured when using various iCloud features:
|In transit||On server|
|Calendars||Yes||Yes||A minimum of 128-bit AES encryption|
|Documents in the Cloud||Yes||Yes|
|Find My iPhone||Yes||Yes|
|Find My Friends||Yes||Yes|
Uses 256-bit AES encryption to store and transmit passwords and credit card information. Also uses elliptic curve asymmetric cryptography and key wrapping.
|iCloud.com||Yes||N/A||All sessions at iCloud.com are encrypted with SSL. Any data accessed via iCloud.com is encrypted on server as indicated in this table.|
|Back to My Mac||Yes||N/A||Back to My Mac does not store data on iCloud. Data retrieved from other computers is encrypted with SSL while in transit.|
|iTunes in the Cloud||Yes||N/A||Purchased or matched music files are not encrypted on server because they do not contain any personal information.|
|Mail and Notes||Yes||No||All traffic between your devices and iCloud Mail and Notes is encrypted with SSL. Consistent with standard industry practice, iCloud does not encrypt data stored on IMAP mail servers. All Apple email clients support optional S/MIME encryption.|
Use of secure tokens for authentication
When you access iCloud services using Apple’s built-in apps (for example, Mail, Contacts, and Calendar apps on iOS or OS X), authentication is handled using a secure token. Using secure tokens eliminates the need to store your iCloud password on devices and computers. Even if you choose to use a third-party application to access your iCloud data, your username and password are sent over an encrypted SSL connection.
When creating an Apple ID to use with iCloud, your password must have a minimum of 8 characters, a number, an uppercase letter, and a lowercase letter. Using a strong password is the most important thing you can do to help keep your data secure. Learn more about creating a strong password.
Apple offers an optional security enhancement for your Apple ID called two-step verification. Two-step verification requires you to verify your identity using one of your devices before you can make changes to your account information at My Apple ID, sign in to iCloud on a new device or at iCloud.com, or make an iTunes, iBooks, or App Store purchase from a new device. Learn more about two-step verification.
Find My iPhone
- You must set up Find My iPhone, iPad, and iPod touch in iOS Settings before your device can be located.
- You must set up Find My Mac in OS X System Preferences before your Mac can be located.
- Location data is sent from your device only when you request its location—it isn't transmitted or recorded at any other time.
- Last known device location data is stored on Apple's servers in an encrypted format for 24 hours and then permanently deleted.
- Lost Mode data is stored on the device that is in Lost Mode and retrieved on-demand by you only.
- You are automatically signed out of the Find My iPhone app (on device or on the web) after 15 minutes of inactivity.
- Remote Lock allows you lock a device's screen to prevent others from accessing your data.
- Remote Wipe lets you permanently and securely erase your data from a device.
- If you’re using Family Sharing, sharing your device's location with family members is optional. You will not share your device's location by default.
Learn more about Find My iPhone.
- With iCloud, you can share your location with friends and family using the Find My Friends app or the built-in Messages app in iOS 8.
- For someone to see your location, you must first give that person explicit permission.
- Your location is sent from your device only when a friend requests to see your location or if you choose to send your current location within a message—it is not transmitted or recorded at any other time.
- There is a single switch you can use to hide from all of your friends at any time. You can turn the option off from either of these settings:
- Settings > Privacy > Location Services > Share My Location
- Settings > iCloud > Share My Location
- Last known location data is stored on Apple's servers in an encrypted format for only 2 hours, and then permanently deleted.
- If you’re using Family Sharing, sharing your location with family members is optional. You will not share your location by default.
- You can share your location with friends and see your friends on a map if you download the optional and free Find My Friends app from the App Store.
Learn more about Find My Friends.
- iCloud Keychain encryption keys are created on your devices, and Apple can't access those keys. Only encrypted keychain data passes through Apple's servers, and Apple can't access any of the key material that could be used to decrypt that data.
- Only trusted devices that you approved can access your iCloud Keychain.
- Advanced settings allow you to choose an iCloud Security Code longer than four digits or have your device generate one for you.
- You can choose to disable keychain recovery, which means that iCloud Keychain is kept up to date across your approved devices, but the encrypted data is not stored with Apple and cannot be recovered if all of your devices are lost.
- You can delete unwanted photos from My Photo Stream at any time.
- You can delete unwanted photos and videos from your shared albums at any time.
- You can remove subscribers from shared albums that you created at any time.
- If you’re using Family Sharing, you will be automatically added to an iCloud Photo Sharing shared album with your family members. However, you're in control of what photos, videos, and comments you want to share. Nothing is shared automatically or by default.
Learn more about iCloud Photo Sharing and My Photo Stream.