How to Enforce TLS Certificate Roles, Prevent MiTM Attacks in iOS Apps

Last updated August 28, 2022 by Appdome

Learn to Enforce Certificate Roles in Mobile apps, in mobile CI/CD with a Data-Driven DevSecOps™ build system.

What are Certificate Roles?

When connecting with remote services, the remote service authenticates its identity by presenting a certificate, which contains the domain to which you connect and the issuer – the “higher” certificate that signed the “lower” certificate.
Signing is a cryptographically safe method that helps testing whether a “lower” certificate was modified. However, as there is no functional difference between certificates, regardless of their roles, each certificate can be used for signing another certificate, thereby approving the entire chain. For example, if your intended domain is signed by *.malicious-domain.com, which is in turn signed by “Go Daddy Secure Certificate Authority – G2”, your application could blindly trust a connection to www.malicious-domain.com.

How does Appdome Enforce Certificate Roles ?

To prevent issues such as the ones mentioned above, where an application blindly and unknowingly trusts a malicious domain, Appdome enforces, in each certificate, the inclusion of a common extension called “Basic-Constraints”, which contains information about the roles of the certificates in the chain.

While enforcing the certificate roles is essential to guaranteeing secure data transfer, if a certificate does not have the Basic-Constraints extension, an SSL (TLS) implementation will not enforce it. Sometimes the source code is not available, and more often the services are on uncontrolled endpoints.

Enforcing Certificate Roles on Mobile apps by Using Appdome

On Appdome, follow these 3 simple steps to create self-defending Mobile Apps that Enforce Certificate Roles without an SDK or gateway:

  1. Upload the Mobile App to Appdome.

    1. Upload an app to Appdome’s Mobile App Security Build System

    2. Upload Method: Appdome Console or DEV-API
    3. Mobile App Formats: .ipa For iOS device or .apk or .aab
  2. Build the Protection: Enforce Certificate Roles.

    1. Building Enforce Certificate Roles by using Appdome’s DEV-API:

      1. Create and name the Fusion Set (security template) that will contain the Enforce Certificate Roles feature as shown below:
      2. fusion set that contains Enforce Certificate Roles

        Figure 1: Fusion Set that will contain the Enforce Certificate Roles feature
        Note: Naming the Fusion Set to correspond to the protection(s) selected is for illustration purposes only (not required).

      3. Follow the steps in Sections 2.2.1-2.2.2 of this article, Building the Enforce Certificate Roles feature via Appdome Console, to add the Enforce Certificate Roles feature to this Fusion Set.

      4. Open the Fusion Set Detail Summary by clicking the “...” symbol on the far-right corner of the Fusion Set, as shown in Figure 1 above, and get the Fusion Set ID from the Fusion Set Detail Summary (as shown below): fusion Set Detail Summary image

        Figure 2: Fusion Set Detail Summary
        Note: Annotating the Fusion Set to identify the protection(s) selected is optional only (not mandatory).

      5. Follow the instructions below to use the Fusion Set ID inside any standard mobile DevOps or CI/CD toolkit like Bitrise, App Center, Jenkins, Travis, Team City, Cirlce CI or other system:
        1. Build an API for the app – for instructions, see the tasks under Appdome API Reference Guide
        2. Look for sample APIs in Appdome’s GitHub Repository
    2. Building the Enforce Certificate Roles feature via Appdome Console

      To build the Enforce Certificate Roles protection by using Appdome Console, follow the instructions below.

      1. Where: Inside the Appdome Console, go to Build > Security Tab > Secure Communication section
      2. How: Toggle (turn ON) Enforce Certificate Roles, as shown belowCertificate Roles, If needed, Customize the Threat Notification to be displayed to the mobile end-user in a standard OS dialog notification when Appdome Enforces . Enforce Certificate Roles option

        Figure 3: Enforce Certificate Roles option
        Note: The App Compromise Notification contains an easy to follow default remediation path for the mobile app end user. You can customize this message as required to achieve brand specific support, workflow or other messaging.

      3. When you select the Enforce Certificate Roles you'll notice that your Fusion Set you created in step 2.1.1 now bears the icon of the protection category that contains Enforce Certificate Roles

        Fusion Set applied Enforce Certificate Roles

        Figure 4: Fusion Set that displays the newly added Enforce Certificate Roles protection

      4. Select the Threat-Event™ in-app mobile Threat Defense and Intelligence policy for Enforce Certificate Roles:
        1. Threat-Events™ OFF > In-App Defense

          If the Threat-Events™ setting is cleared (not selected). Appdome will detect and defend the user and app by enforcing Enforce Certificate Roles.

        2. Threat-Events™ ON > In-App Detection

          When this setting is used, Appdome detects the lack of a “Basic-Constraints” extension and passes Appdome’s Threat-Event™ attack intelligence to the app’s business logic for processing, enforcement, and user notification. For more information on consuming and using Appdome Threat-Events™ in the app, see section Using Threat-Events™ for Enforce Certificate Roles Intelligence and Control in Mobile Apps.

        3. Threat-Events™ ON > In-App Defense

          When this setting is used, Appdome detects and defends against Certificate Roles (same as Appdome Enforce) and passes Appdome’s Threat-Event™ attack intelligence the app’s business logic for processing. For more information on consuming and using Appdome Threat-Events™ in the app, see section Using Threat-Events™ for Enforce Certificate Roles Intelligence and Control in Mobile Apps.

      5. Click Build My App at the bottom of the Build Workflow (shown in Figure 3).
    Congratulations!  The Enforce Certificate Roles protection is now added to the mobile app
  3. Certify the Enforce Certificate Roles feature in Mobile Apps.

    After building Enforce Certificate Roles, Appdome generates a Certified Secure™ certificate to guarantee that the Enforce Certificate Roles protection has been added and is protecting the app. To verify that the Enforce Certificate Roles protection has been added to the mobile app, locate the protection in the Certified Secure™ certificate as shown below: Enforce Certificate Roles shown in Certificate secure

    Figure 5: Certified Secure™ certificate

    Each Certified Secure™ certificate provides DevOps and DevSecOps organizations the entire workflow summary, audit trail of each build, and proof of protection that Enforce Certificate Roles has been added to each Mobile app. Certified Secure provides instant and in-line DevSecOps compliance certification that Enforce Certificate Roles and other mobile app security features are in each build of the mobile app

Using Threat-Events™ for Certificate Roles Intelligence and Control in Mobile Apps

Appdome Threat-Events™ provides consumable in-app mobile app attack intelligence and defense control when Certificate Roles is detected. To consume and use Threat-Events™ for Certificate Roles in Mobile Apps, use AddObserverForName in Notification Center, and the code samples for Threat-Events™ for Certificate Roles shown below.

The specifications and options for Threat-Events™ for Certificate Roles are:

Threat-Event™ Elements Enforce Certificate Roles Method Detail
Appdome Feature Name Enforce Certificate Roles
Threat-Event Mode
OFF, IN-APP DEFENSE Appdome detects, defends and notifies user (standard OS dialog) using customizable messaging.
ON, IN-APP DETECTON Appdome detects the attack or threat and passes the event in a standard format to the app for processing (app chooses how and when to enforce).
ON, IN-APP DEFENSE Uses Appdome Enforce mode for any attack or threat and passes the event in a standard format to the app for processing (gather intel on attacks and threats without losing any protection).
Certified Secure™ Threat Event Check
Visible in ThreatScope™
Developer Parameters for Enforcing Certificate Roles Threat-Event™
Threat-Event NAME SslInvalidCertificateChain
Threat-Event DATA reasonData
Threat-Event CODE reasonCode
Threat-Event REF 6506
Threat-Event SCORE
currentThreatEventScore Current Threat-Event score
threatEventsScore Total Threat-events score
Threat-Event Context Keys
messageMessage displayed for the user on event
externalIDThe external ID of the event which can be listened via Threat Events
osVersionOS version of the current device
deviceModelCurrent device model
deviceManufacturerThe manufacturer of the current device
fusedAppTokenThe task ID of the Appdome fusion of the currently running app
kernelInfoInfo about the kernel: system name, node name, release, version and machine.
carrierPlmnPLMN of the device
deviceIDCurrent device ID
reasonCodeReason code of the occured event
buildDateAppdome fusion date of the current application
devicePlatformOS name of the current device
carrierNameCarrier name of the current device
updatedOSVersionIs the OS version up to date
deviceBrandBrand of the device
deviceBoardBoard of the device
buildUserBuild user
buildHostBuild host
sdkVersionSdk version
timeZoneTime zone
deviceFaceDownIs the device face down
locationLongLocation long
locationLatLocation lat
locationStateLocation state
wifiSsidWifi SSID
wifiSsidPermissionStatusWifi SSID permission status
hostFailed host
DeveventDetailedErrorMessageError message
extendedMessageTextExtended message
certificateCNCertificate common name
certificateSHA1Certificate SHA1

With Threat-Events™ enabled (turned ON), Mobile developers can get detailed attack intelligence and granular defense control in Mobile applications and create amazing user experiences for all mobile end users when Certificate Roles is detected.

The following is a code sample for native Mobile apps, which uses all values in the specification above for Enforce Certificate Roles:

Prerequisites to Using Enforce Certificate Roles:

To use Appdome’s mobile app security build system to Enforce Certificate Roles , you’ll need:

Using Appdome, there are no development or coding prerequisites to build secured Apps by using Enforce Certificate Roles. There is no SDK and no library to code or implement in the app and no gateway to deploy in your network. All protections are built into each app and the resulting app is self-defending and self-protecting.

Releasing and Publishing Mobile Apps with Enforce Certificate Roles

After successfully securing your app by using Appdome, there are several available options to complete your project, depending on your app lifecycle or workflow. These include:

All apps protected by Appdome are fully compatible with any public app store, including Apple App Store, Google Play, Huawei App Gallery and more.

Protections Similar to Enforce Certificate Roles

Here are a few related resources:

If you have any questions, please send them our way at support.appdome.com or via the chat window on the Appdome platform.

Thank you!

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