+MASTG-BEST-0024 Store Data Encrypted in App Sandbox Directory (iOS)

MASTG-BEST-0024 Store Data Encrypted in App Sandbox Directory (iOS)

Platform: iOS
Knowledge: MASTG-KNOW-0108

Choose the right location for storing the app's and the user's data to the app sandbox: use Documents directory to store user-generated content and Library directory for app's internal data.

An app can be configured to make Documents directory accessible to the user in the Files app by setting UIFileSharingEnabled and LSSupportsOpeningDocumentsInPlace. Therefore, storing databases, config files, purchase state in this directory is highly dangerous because:

a user can tamper with internal app files
an attacker with a physical access to the device can copy content of Documents directory
other apps can access Documents directory of other apps with a document picker interface

Note: Storing data in the correct directory doesn't mean it's secure. For L2 profile apps, it's recommended to encrypt the files before storing them, and put the encryption key into the Keychain.

1. Oversigt

Titel	Standard

1.1 Referencer

1.2 Identificerede krav

1.3 Relaterede reguleringer

2. Identificerede krav

Krav
Kilde	Krav

3. Relaterede reguleringer

Reguleringer
Kilde	Regulering

Linkede sager

Sagslinks
Linktype	Sag
is related to	MASTG-TEST-0299 Data Protection Classes for Files in Private Storage (iOS)
is related to	MASTG-TEST-0300 References to APIs for Storing Unencrypted Data in Private Storage (iOS)
is related to	MASTG-TEST-0301 Runtime Use of APIs for Storing Unencrypted Data in Private Storage (iOS)
is related to	MASTG-TEST-0302 Sensitive Data Unencrypted in Private Storage Files (iOS)
is related to	MASTG-TEST-0303 References to APIs for Storing Unencrypted Data in Shared Storage (iOS)

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