Prevent Strandhogg Task Hijacking

Learn to Prevent Strandhogg Task Hijacking in Android apps, in mobile CI/CD with a Data-Driven DevSecOps™ build system.

What is Strandhogg Task Hijacking?

The Strandhogg Task Hijacking attack is based on the way an application handles its activities. This type of attack can take place if the app is designed to allow exported activities – namely, activities that can be accessed by external components or apps – start (launch) onto the app as tasks.

A ‘task’ is a collection of activities the user interacts with when trying to do something within the app. These activities are arranged in a stack called the back stack in the order in which each activity is opened. For example: An online stock trading app may display multiple shares. Clicking on a share opens another screen, which allows several activities. Clicking ‘Deposit’ opens a deposit window and so on.
By using StrandHogg, malicious actors can gain access to personal, confidential information such as login credentials, phone conversations, SMS messages and photos.

How does Appdome Prevent Strandhogg Task Hijacking?

To prevent a scenario in which malicious apps misuse these exported activities for performing various harmful actions, Appdome prevents the attack from happening by adjusting the task usage of the app so its windows cannot be exploited by an attacking app.
These features lock the activities within the app and will Prevent Strandhogg Task Hijacking attempt when the app is in the foreground.

Prevent Strandhogg Task Hijacking on Android apps using Appdome

On Appdome, follow these 3 simple steps to create self-defending Android Apps that Prevent Strandhogg Task Hijacking 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. Android Formats: .apk or .aab
   4. Prevent Strandhogg Task Hijacking Compatible With: Java, JS, C++, C#, Kotlin, Flutter, React Native, Unity, Xamarin, Cordova and more

2. Build the feature: Prevent Strandhogg Task Hijacking.

   1. Building Prevent Strandhogg Task Hijacking by using Appdome’s DEV-API:

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

      Figure 1: Fusion Set that will contain the Prevent Strandhogg Task Hijacking 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 Strandhogg Task Hijacking feature via Appdome Console, to add the Prevent Strandhogg Task Hijacking 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 Strandhogg Task Hijacking feature via Appdome Console

      To build the Prevent Strandhogg Task Hijacking protection by using Appdome Console, follow the instructions below.

      1. Where: Inside the Appdome Console, go to Build > Anti Fraud Tab > Mobile Malware Prevention section
      2. How: Toggle (turn ON) Prevent Strandhogg Task Hijacking, as shown below.
         If needed, Customize the Threat Notification to be displayed to the mobile end-user in a standard OS dialog notification when Appdome Prevents Strandhogg Task Hijacking.

         Figure 3: Prevent Strandhogg Task Hijacking 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 Prevent Strandhogg Task Hijacking 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 Strandhogg Task Hijacking

         

         Figure 4: Fusion Set that displays the newly added Prevent Strandhogg Task Hijacking protection

      4. Optional Configuration with Prevent Strandhogg Task Hijacking:

         1. Trust Specified Activities Only

            Specify the class name of the activity to exclude from Overlay detection

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

   Congratulations!  The Prevent Strandhogg Task Hijacking protection is now added to the mobile app

3. Certify the Prevent Strandhogg Task Hijacking feature in Android Apps.

   After building Prevent Strandhogg Task Hijacking, Appdome generates a Certified Secure™ certificate to guarantee that the Prevent Strandhogg Task Hijacking protection has been added and is protecting the app. To verify that the Prevent Strandhogg Task Hijacking 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 Strandhogg Task Hijacking has been added to each Android app. Certified Secure provides instant and in-line DevSecOps compliance certification that Prevent Strandhogg Task Hijacking and other mobile app security features are in each build of the mobile app