How to Prevent Code Tampering in Android & iOS Apps

Learn to Prevent code tampering in Mobile apps, in mobile CI/CD with a Data-Driven DevSecOps™ build system.

What is code tampering?

Tampering involves the modification of a mobile app (either the compiled app or the running process), or the mobile app’s environment, thereby affecting the app behavior. For example, an app might not run on your rooted test device, thus preventing any option to run some of your tests.

Why Prevent code tampering in Mobile Apps?

Tamper prevention protects your app against unwanted changes, mods, and hacks – all without adding development work or time to your release cycles. This is done by sealing your app and actively detecting modifications during initialization and at multiple other points during run-time (whenever the app is being used).
Mobile Anti-Tampering protects against the following static and dynamic modifications to the application:

• Re-signing the application.
• Attempting to Modify the Appdome adapter.
• Modifying the application’s main executable (app binary – ipa in iOS and DEX file in Android).

Prerequisites to Using Prevent Code Tampering:

To use Appdome’s mobile app security build system to Prevent code tampering , you’ll need:

• Appdome account (create a free Appdome account here)
• A license for Prevent Code Tampering
• Mobile App (.ipa For iOS device or .apk or .aab For Mobile)
• Signing Credentials (see Signing Secure Android apps and Signing Secure iOS apps)

Prevent code tampering on Mobile apps using Appdome

On Appdome, follow these 3 simple steps to create self-defending Mobile Apps that Prevent code tampering 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
   4. Prevent Code Tampering Compatible With: Obj-C, C+, Java, JS, C#, C++, Swift, Kotlin, Flutter, React Native, Unity, Xamarin, and more

2. Build the feature: Prevent Code Tampering.

   1. Building Prevent Code Tampering by using Appdome’s DEV-API:

      1. Create and name the Fusion Set (security template) that will contain the Prevent Code Tampering feature as shown below:
      

      Figure 1: Fusion Set that will contain the Prevent Code Tampering 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 2.2.1-2.2.2 of this article, Building the Prevent Code Tampering feature via Appdome Console, to add the Prevent Code Tampering feature to this Fusion Set.

      3. 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):

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

      4. 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 Prevent Code Tampering feature via Appdome Console

      To build the Prevent Code Tampering protection by using Appdome Console, follow the instructions below.

      1. Where: Inside the Appdome Console, go to Build > Security Tab > ONEShield™ section . Like all other options in ONEShield™, Prevent Code Tampering is turned on by default, as shown below:

         Figure 3: Prevent Code Tampering 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.

      2. When you select the Prevent Code Tampering you'll notice that your Fusion Set you created in step 2.1.1 now bears the icon of the protection category that contains Prevent Code Tampering

         

         Figure 4: Fusion Set that displays the newly added Prevent Code Tampering protection

      3. Extra Configuration with Prevent Code Tampering:

         1. Checksum Validation

         2. App Integrity/Structure Scan

         3. Prevent Static App Patching

         4. Prevent Code Tampering

         5. Prevent App Repacking

      4. Click Build My App at the bottom of the Build Workflow (shown in Figure 3).

   Congratulations!  The Prevent Code Tampering protection is now added to the mobile app

3. Certify the Prevent Code Tampering feature in Mobile Apps.

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

   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 Prevent Code Tampering has been added to each Mobile app. Certified Secure provides instant and in-line DevSecOps compliance certification that Prevent Code Tampering and other mobile app security features are in each build of the mobile app