How to Use App Store Signature Validation in iOS Apps

Last updated May 7, 2024 by Appdome

This Knowledge Base article describes how to use Appdome’s AI/ML in your CI/CD pipeline to continuously deliver plugins that Validate App Store Signature in iOS apps.

Why Should Developers Prevent the Running of non-authorized apps?

Fraudsters and other cyber-criminals often use various methods and techniques to create fake apps by copying or cloning existing popular apps and then repackaging, re-signing, and re-distributing those apps on alternative, malicious or non-approved app stores. It is fairly easy for malicious actors to publish fake, malicious or pirated apps on app stores other than Apple’s App Store. They only need to download a target app (such as your app) on a Jailbroken mobile device, modify the app, and then repackage, re-sign, and re-distribute the fake or pirated mobile app to any app store they want.

How does Appdome Prevent the Running of non-Authorized Apps?

Appdome App Store Validation validates that apps signed for Apple App Store cannot be distributed through any other app stores. If the original app was signed for Apple’s App Store, Appdome prevents the app from being re-signed with a different application identifier. If the app was originally published to the app store, and the application identifier is different than the originally signed app, Appdome detects the difference and prevents the app from running.

Prerequisites for Using Appdome's App Store Signature Validation Plugins:

To use Appdome’s mobile app security build system to Validate App Store Signature , you’ll need:

How to Implement Validate App Store Signature in iOS Apps Using Appdome

On Appdome, follow these 3 simple steps to create self-defending iOS Apps that Validate App Store Signature without an SDK or gateway:

  1. Designate the Mobile App to be protected.

    1. Upload an app via the Appdome Mobile Defense platform GUI or via Appdome’s DEV-API or CI/CD Plugins.

    2. iOS Formats: .ipa
    3. App Store Signature Validation is compatible with: Obj-C, Java, Swift, Flutter, React Native, Unity, Xamarin, Cordova and other iOS apps.
  2. Select the defense: App Store Signature Validation.

      1. Create and name the Fusion Set (security template) that will contain the App Store Signature Validation feature as shown below:
        fusion set that contains App Store Signature Validation .

        Figure 1: Fusion Set that will contain the App Store Signature Validation feature
        Note: Naming the Fusion Set to correspond to the protection(s) selected is for illustration purposes only (not required).

      2. Follow the steps in Sections 2.2-2.2.2 of this article to add the App Store Signature Validation feature to your Fusion Set via the Appdome Console.

      3. When you select the App Store Signature Validation you'll notice that the Fusion Set you created in step 2.1 now bears the icon of the protection category that contains App Store Signature Validation.

        Fusion Set applied App Store Signature Validation

        Figure 2: Fusion Set that displays the newly added App Store Signature Validation protection
        Note: Annotating the Fusion Set to identify the protection(s) selected is optional only (not mandatory).

      4. Open the Fusion Set Detail Summary by clicking the “...” symbol on the far-right corner of the Fusion Set. Copy the Fusion Set ID from the Fusion Set Detail Summary (as shown below): fusion Set Detail Summary image

        Figure 3: Fusion Set Detail Summary

      5. Follow the instructions below to use the Fusion Set ID inside any standard mobile DevOps or CI/CD toolkit like Bitrise, Jenkins, Travis, Team City, Circle CI or other system:
        1. Refer to the Appdome API Reference Guide for API building instructions.
        2. Look for sample APIs in Appdome’s GitHub Repository.
    1. Add the App Store Signature Validation feature to your security template.

      1. Navigate to Build > Anti Fraud tab > Social Engineering Prevention section in the Appdome Console.
      2. Toggle On > App Store Signature Validation.

        (a) Choose to monitor this attack vector by checking the Threat Events checkbox associated with App Store Signature Validation as shown below.

        (b) To receive mobile Threat Monitoring, check the ThreatScope™ box as shown below. For more details, see our knowledge base article on ThreatScope™ Mobile XDR.
        App Store Signature Validation option

        Figure 4: Selecting Validate App Store Signature

        Note: The Appdome Platform displays the Mobile Operation Systems supported by each defense in real-time. For more details, see our OS Support Policy KB.

      3. Select the Threat-Event™ in-app mobile Threat Defense and Intelligence policy for App Store Signature Validation:
        1. Threat-Events™ OFF > In-App Defense

          If the Threat-Events™ setting is not selected. Appdome will detect and defend the user and app by enforcing App Store Signature.

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

          When this setting is used, Appdome detects an attempt to install an app from a non-official App Store. 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™ to App Store Signature ValidationValidate Intelligence and Control in Mobile Apps.

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

          When this setting is used, Appdome detects and defends against App Store Signature (same as Appdome Enforce) and passes Appdome’s Threat-Event™ attack intelligence to 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 App Store Signature ValidationValidate Intelligence and Control in Mobile Apps.

      4. Configure the User Experience Options for App Store Signature Validation:
        With Threat-Events™ OFF, Appdome provides several user experience options for mobile brands and developers.
        1. App Compromise Notification: Customize the pop-up or toast Appdome uses to notify the user when a threat is present while using the protected mobile app.
        2. Short message Option. This is available for mobile devices that allow a banner notification for security events.
        3. Localized Message Option. Allows Appdome users to support global languages in security notifications.

          Localized Message

          Figure 5: Default User Experience Options for Appdome’s App Store Signature

        4. App Store Signature Validation Threat Code™. Appdome uses AI/ML to generate a unique code each time App Store Signature Validation is triggered by an active threat on the mobile device. Use the code in Appdome Threat Resolution Center™ to help end users identify, find and resolve active threats on the personal mobile devices.
    2. Initiate the build command either by clicking Build My App at the bottom of the Build Workflow (shown in Figure 4) or via your CI/CD as described in Section 2.1.4.
    Congratulations!  The App Store Signature Validation protection is now added to the mobile app
  3. Certify the App Store Signature Validation feature in iOS Apps

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

    Figure 6: 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 App Store Signature Validation has been added to each iOS app. Certified Secure provides instant and in-line DevSecOps compliance certification that App Store Signature Validation and other mobile app security features are in each build of the mobile app.

Using Threat-Events™ for App Store Signature Intelligence and Control in iOS Apps

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

The specifications and options for Threat-Events™ for App Store Signature are:

Threat-Event™ Elements Validate App Store Signature Method Detail
Appdome Feature Name App Store Signature Validation
Threat-Event Mode
OFF, IN-APP DEFENSE Appdome detects, defends and notifies user (standard OS dialog) using customizable messaging.
ON, IN-APP DETECTION 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 Validating App Store Signature Threat-Event™
Threat-Event NAME NotInstalledFromOfficialStore
Threat-Event DATA reasonData
Threat-Event CODE reasonCode
Threat-Event REF 6902
Threat-Event SCORE
currentThreatEventScore Current Threat-Event score
threatEventsScore Total Threat-events score
Threat-Event Context Keys
message Message displayed for the user on event
failSafeEnforce Timed enforcement against the identified threat
externalID The external ID of the event which can be listened via Threat Events
osVersion OS version of the current device
deviceModel Current device model
deviceManufacturer The manufacturer of the current device
fusedAppToken The task ID of the Appdome fusion of the currently running app
kernelInfo Info about the kernel: system name, node name, release, version and machine.
deviceID Current device ID
reasonCode Reason code of the occurred event
buildDate Appdome fusion date of the current application
devicePlatform OS name of the current device
updatedOSVersion Is the OS version up to date
timeZone Time zone
deviceFaceDown Is the device face down
locationLong Location longitude conditioned by location permission
locationLat Location latitude conditioned by location permission
locationState Location state conditioned by location permission
wifiSsid Wifi SSID
wifiSsidPermissionStatus Wifi SSID permission status
threatCode The last six characters of the threat code specify the OS, allowing the Threat Resolution Center to address the attack on the affected device.

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


The following is a code sample for native iOS apps, which uses all values in the specification above for App Store Signature Validation:


Important! Replace all placeholder instances of <Context Key> with the specific name of your threat event context key across all language examples. This is crucial to ensure your code functions correctly with the intended event data. For example, The <Context Key> could be the message, externalID, OS Version, reason code, etc.



Using Appdome, there are no development or coding prerequisites to build secured iOS Apps by using App Store Signature Validation. 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 App Store Signature Validation

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:

Related Articles:

How Do I Learn More?

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!

Thanks for visiting Appdome! Our mission is to secure every app on the planet by making mobile app security easy. We hope we’re living up to the mission with your project.

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