Apple iOS must not allow backup to remote systems (iCloud Keychain).

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-71787	AIOS-02-080004	SV-86411r1_rule		Medium

Description
The iCloud Keychain is an Apple iOS function that will store users' account names and passwords in iCloud and then synchronize this data among the users' Macs, iPhones, and iPads. An adversary may use any of the stored iCloud keychain passwords after unlocking one of the synchronized devices. If a user is synchronizing devices, the user must protect all of the devices to prevent unauthorized use of the passcodes. Moreover, the keychain being transmitted through the cloud opens the possibility that a well-resourced, sophisticated adversary could compromise the cloud-transmitted keychain. Not allowing the iCloud Keychain feature mitigates the risk of the encrypted set of passwords being compromised when transmitted through the cloud or synchronized across multiple devices. SFR ID: FMT_SMF_EXT.1.1 #40

Description

The iCloud Keychain is an Apple iOS function that will store users' account names and passwords in iCloud and then synchronize this data among the users' Macs, iPhones, and iPads. An adversary may use any of the stored iCloud keychain passwords after unlocking one of the synchronized devices. If a user is synchronizing devices, the user must protect all of the devices to prevent unauthorized use of the passcodes. Moreover, the keychain being transmitted through the cloud opens the possibility that a well-resourced, sophisticated adversary could compromise the cloud-transmitted keychain. Not allowing the iCloud Keychain feature mitigates the risk of the encrypted set of passwords being compromised when transmitted through the cloud or synchronized across multiple devices. SFR ID: FMT_SMF_EXT.1.1 #40

STIG	Date
Apple iOS 10 Security Technical Implementation Guide	2016-11-22

Details

Check Text ( C-72047r1_chk )
Review configuration settings to confirm iCloud keychain is disabled. This check procedure is performed on both the Apple iOS management tool and the Apple iOS device. Note: If an organization has multiple configuration profiles, the check procedure must be performed on the relevant configuration profiles applicable to the scope of the review. In the Apple iOS management tool, verify "Allow iCloud keychain" is unchecked. Alternatively, verify the text "allowCloudKeychainSync" appears in the configuration profile (.mobileconfig file). On the Apple iOS device: 1. Open the Settings app. 2. Tap "General". 3. Tap "Profiles" or "Profiles & Device Management" or "Device Management". 4. Tap the Configuration Profile from the iOS management tool containing the management policy. 5. Verify "iCloud Keychain not allowed" is listed. If "Allow iCloud keychain" is checked in the Apple iOS management tool, "allowCloudKeychainSync" appears in the configuration profile, or "iCloud Keychain not allowed" is not listed on the Apple iOS device, this is a finding.

Check Text ( C-72047r1_chk )

Review configuration settings to confirm iCloud keychain is disabled.

This check procedure is performed on both the Apple iOS management tool and the Apple iOS device.

Note: If an organization has multiple configuration profiles, the check procedure must be performed on the relevant configuration profiles applicable to the scope of the review.

In the Apple iOS management tool, verify "Allow iCloud keychain" is unchecked.

Alternatively, verify the text "allowCloudKeychainSync" appears in the configuration profile (.mobileconfig file).

On the Apple iOS device:
1. Open the Settings app.
2. Tap "General".
3. Tap "Profiles" or "Profiles & Device Management" or "Device Management".
4. Tap the Configuration Profile from the iOS management tool containing the management policy.
5. Verify "iCloud Keychain not allowed" is listed.

If "Allow iCloud keychain" is checked in the Apple iOS management tool, "allowCloudKeychainSync" appears in the configuration profile, or "iCloud Keychain not allowed" is not listed on the Apple iOS device, this is a finding.

Fix Text (F-78139r1_fix)
Install a configuration profile to disable iCloud keychain.