How to Block Mobile Bots with Client Certificates

Last updated September 24, 2024 by Appdome

Learn to Protect Mobile Client Certificates in Mobile apps, in mobile CI/CD with a Data-Driven DevSecOps™ build system.

What Threat Do Non-Validated Mobile Apps Pose?

Important: Service for the Mobile Client Certificate feature has ended as of December 31st, 2023.
We invite you to upgrade to our Mobile Bot Defense solution for enhanced mobile app security. For more information, please contact our support team at support.appdome.com.

Mobile apps connect to all sorts of external services. They connect to their host server to perform tasks such as authenticating users, downloading content, and connecting to other mobile resources. Mobile apps also connect to 3rd-party services embedded in the app, such as payment providers, analytics vendors, location services, and more. As a mobile app connects with the outside world, hackers and malicious parties exploit weaknesses in the communications or transport layer to conduct network-based attacks that target the mobile application’s backend. For example, attackers often use techniques like session hijacking, fake or forged digital certificates, or automated malicious bots or scripts. These techniques are designed to attack infrastructure by using click fraud, credential stuffing, or other large-scale automated attacks.

How do Mobile Client Certificates Work?

Using Appdome’s no-code mobile app security platform, you can embed the trusted, approved client certificates (client P12/PKCS) inside the application, where they are securely stored (encrypted using AES-256). For every connection, the application presents its unique certificate along with a unique password/secret to the server for inspection and validation as part of the SSL/TLS handshake. The server then inspects the certificate using its private key to ensure that it matches, in which case the server knows it can trust the client/app and establish a secure session. This protects the backend servers and infrastructure against connections originating from compromised endpoints or malicious bots. In order to use Appdome’s Mobile Client Certificates feature, the server must be configured to validate incoming connections based on client certificates.

Prerequisites for Using Mobile Client Certificates:

To use Appdome’s mobile app security build system to Protect Mobile Client Certificates , you’ll need:

Protect Mobile Client Certificates on Mobile apps using Appdome

On Appdome, follow these 3 simple steps to create self-defending Mobile Apps that Protect Mobile Client Certificates 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, or .apk or .aab for Android
    4. Mobile Client Certificates Compatible With: Obj-C, Java, JS, C#, C++, Swift, Kotlin, Flutter, React Native, Unity, Xamarin, and more
  2. Build the feature: Mobile Client Certificates.

    1. Building Mobile Client Certificates by using Appdome’s DEV-API:

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

        Figure 1: Fusion Set that will contain the Mobile Client Certificates 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 Mobile Client Certificates feature via Appdome Console, to add the Mobile Client Certificates 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. Copy 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, Circle 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 Mobile Client Certificates feature via Appdome Console

      To build the Mobile Client Certificates 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: Check whether is toggled On (enabled), otherwise enable it . The feature Mobile Client Certificates is enabled by default, as shown below. Toggle (turn ON) Mobile Client Certificates, as shown below. Mobile Client Certificates option

        Figure 3: Protect Mobile Client Certificates option

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

        Fusion Set applied Mobile Client Certificates

        Figure 4: Fusion Set that displays the newly added Mobile Client Certificates protection

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

    After building Mobile Client Certificates, Appdome generates a Certified Secure™ certificate to guarantee that the Mobile Client Certificates protection has been added and is protecting the app. To verify that the Mobile Client Certificates protection has been added to the mobile app, locate the protection in the Certified Secure™ certificate as shown below: Mobile Client Certificates 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 Mobile Client Certificates has been added to each Mobile app. Certified Secure provides instant and in-line DevSecOps compliance certification that Mobile Client Certificates and other mobile app security features are in each build of the mobile app

Using Threat-Events™ for Mobile Client Certificates Intelligence and Control in Mobile Apps

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

The specifications and options for Threat-Events™ for Mobile Client Certificates are:

Threat-Event™ Elements Protect Mobile Client Certificates Method Detail
Appdome Feature Name Mobile Client Certificates
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 x
Visible in ThreatScope™ x
Developer Parameters for Protecting Mobile Client Certificates Threat-Event™
Threat-Event NAME
Threat-Event DATA reasonData
Threat-Event CODE reasonCode
Threat-Event REF
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.
carrierPlmn PLMN of the device. Only available for Android devices.
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
carrierName Carrier name of the current device. Only available for Android.
updatedOSVersion Is the OS version up to date
deviceBrand Brand of the device
deviceBoard Board of the device
buildUser Build user
buildHost Build host
sdkVersion Sdk version
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), 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 Mobile Client Certificates are detected.


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


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 Mobile Apps by using Mobile Client Certificates. 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 Mobile Client Certificates

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:

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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