Block Interface Hijacking

Learn to Block interface hijacking in Android apps, in mobile CI/CD with a Data-Driven DevSecOps™ build system.

What is Interface Hijacking?

The interface hijack 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.

Task means a collection of activities with which users interact when trying to do something in your 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 a share opens another screen, which allows several activities. Clicking Deposit opens a deposit window and so on.

To prevent a scenario where 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.

How does Appdome Block Interface Hijacking?

To prevent interface hijacking, you need to enable the feature Block App Overlay Attacks and then enable the sub-feature Block Interface Hijacking. These features lock the activities in the app and will block an interface hijack attempt when the app is in the foreground.

Note:

To prevent any risk of app hijacking, you are also strongly recommended to enable the feature Prevent StrandHogg. This feature block attackers’ attempts to use malicious apps that assume the identity of legitimate apps while also remaining completely hidden. By using StrandHogg, malicious actors can gain access to personal, confidential information such as login credentials, phone conversations, SMS messages and photos.

Depending on the attack vector used, you may also be advised to enable the following features:

• Prevent Auto-clickers

Auto-Clicking Apps (aka: Click bots) are automated programs used to automate processes with malicious intent by sending touch events repeatedly.

• Prevent Team Viewer

Malicious actors could set up a phishing site with a malicious iframe, which would launch the TeamViewer client when the victim opened the website. What makes the vulnerability especially dangerous is that it would happen with little input from the user.

Blocking interface hijacking on Android apps by Using Appdome

On Appdome, follow these 3 simple steps to create self-defending Android Apps that Block interface 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

2. Build the feature: Block Interface Hijacking.

   1. Building Block Interface Hijacking by using Appdome’s DEV-API:

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

      Figure 1: Fusion Set that will contain the Block Interface 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 Block Interface Hijacking feature via Appdome Console, to add the Block Interface 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 Block Interface Hijacking feature via Appdome Console

      To build the Block Interface Hijacking protection by using Appdome Console, follow the instructions below.

      1. Where: Inside the Appdome Console, go to Build > Anti Fraud Tab > Mobile Fraud Prevention section
      2. How: Toggle (turn ON) Block Interface 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 Blocks interface hijacking.

         Figure 3: Block interface 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 Block Interface 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 Block Interface Hijacking

         

         Figure 4: Fusion Set that displays the newly added Block Interface Hijacking protection

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

   Congratulations!  The Block Interface Hijacking protection is now added to the mobile app

3. Certify the Block Interface Hijacking feature in Android Apps.

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