How to Validate a Nonce Payload with Appdome's MobileBOT™ Defense Using AI

Last updated August 6, 2025 by Appdome

This Knowledge Base article describes how to use Appdome’s AI in your CI/CD pipeline to continuously deliver plugins that Validate Nonce in Payload in Mobile apps.

What Is a Nonce Payload?

A Nonce Payload is a unique, one-time token generated during session initiation or at key transaction points in mobile applications. Its primary function is to prevent replay attacks, where intercepted requests are duplicated by malicious actors. Replay attacks often occur during man-in-the-middle (MiTM) scenarios or through automated bot activities, where attackers attempt to re-use valid requests to gain unauthorized access or privileges. The Nonce Payload ensures that each session or transaction is assigned a one-time identifier, making it impossible for attackers to replicate legitimate requests without detection, thus maintaining the integrity of communications between the app and server. Without the Nonce Payload, attackers could more easily manipulate session data, exposing apps to significant security risks, including data breaches, unauthorized financial transactions, and violation of data privacy laws.

How Appdome Protects Mobile Apps with Nonce Payload

Appdome’s MobileBOT™ Defense integrates Nonce Payload validation into its Anti-Bot Payload mechanism, ensuring secure, one-time token generation during critical points in the app’s operation. When the Nonce Payload is generated, it is securely transmitted to the server, where it is validated. If any attempt to replay or reuse the token is detected, Appdome invalidates the session and prevents further communication. This process not only stops replay attacks but also enhances the overall security framework by ensuring that each session remains unique and valid, thus preventing unauthorized access and maintaining the app’s integrity.

Prerequisites for Using Appdome's Nonce in Payload Plugins:

To use Appdome’s mobile app security build system to Validate Nonce in Payload , you’ll need:

How to Implement Validate Nonce in Payload in Mobile Apps Using Appdome

On Appdome, follow these simple steps to create self-defending Mobile Apps that Validate Nonce in Payload 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. Mobile App Formats: .ipa for iOS, or .apk or .aab for Android
    3. Nonce in Payload is compatible with: Obj-C, Java, JS, C#, C++, Swift, Kotlin, Flutter, React Native, Unity, Xamarin, and more.
  2. Select the defense: Nonce in Payload.

      1. Create and name the Fusion Set (security template) that will contain the Nonce in Payload feature as shown below:
        fusion set that contains Nonce in Payload

        Figure 1: Fusion Set that will contain the Nonce in Payload feature

      2. Follow the steps in Sections 2.2-2.2.2 of this article to add the Nonce in Payload feature to your Fusion Set via the Appdome Console.

      3. When you enable Session Risk you'll notice that the Fusion Set you created in step 2.1 now bears the icon of the protection category that contains Nonce in Payload.

        Fusion Set applied Nonce in Payload

        Figure 2: Fusion Set that displays the newly added Nonce in Payload 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 Nonce in Payload feature to your security template.

      1. Navigate to Build > Anti Bot tab > MobileBOT™ Defense section in the Appdome Console.
      2. Toggle On Session Risk > Nonce in Payload.
        Note: The checkmark feature Nonce in Payload is enabled by default, as shown below. Nonce in Payload option

        Figure 4: Selecting Validate Nonce in Payload

    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 Nonce in Payload protection is now added to the mobile app
  3. Certify the Nonce in Payload feature in Mobile Apps

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

Using Threat-Events™ for Nonce in Payload Intelligence and Control in Mobile Apps

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

The specifications and options for Threat-Events™ for Nonce in Payload are:

Threat-Event™ Elements Validate Nonce in Payload Method Detail
Appdome Feature Name Nonce in Payload
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 Validating Nonce in Payload Threat-Event™
Threat-Event NAME
Threat-Event DATA reasonData
Threat-Event CODE reasonCode
Threat-Event SCORE
currentThreatEventScore Current Threat-Event score
threatEventsScore Total Threat-events score
Threat-Event Context Keys
Timestamp The exact time the threat event was triggered, recorded in milliseconds since epoch
message Message displayed for the user on event
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
deviceBrand Brand of the device
deviceBoard Board of the device
buildUser Build user
buildHost Build host
sdkVersion Sdk version
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 Nonce in Payload is detected.


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


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 Nonce in Payload. 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 Nonce in Payload

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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