How to Block Non-SSL Connections in Android Apps

Last updated November 22, 2023 by Appdome

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

What is a Non-SSL Connection?

Non-SSL Connections are connections that do not use SSL/TLS encryption and typically use the HTTP protocol. Packets in connections that are being sent through this protocol contain clear text, which makes these packets insecure and prone to vulnerabilities. A common example of such vulnerabilities are man-in-the-middle attacks, which allow eavesdropping and tampering with the content. While nowadays most sites already switched to HTTPS protocol that uses SSL/TLS, some are still using regular HTTP to take advantage of the initial connection speed. When a connection is established via HTTP, it does not perform an SSL handshake to begin the connection. The use of HTTP is mainly common in connections where the performance and the user experience is the most important, while the outgoing contents of the connection packets do not contain sensitive data like ads.

Why Block Non-SSL Connections?

Data in Non-SSL connections may contain sensitive information, such as tokens and cookies related to user logins, device info, user input, and passwords. Blocking non-SSL connections by enabling the Android MiTM Prevention feature is important even if the app only accesses SSL/TLS based URLs. To enhance security, it’s crucial to block all non-SSL connections, even if the app primarily accesses SSL/TLS-based URLs. These URLs might still load content via plain HTTP requests, which can be altered, potentially putting your users at risk. For example, someone could request sensitive user data from a database. Additionally, URLs without TLS/SSL extension don’t undergo authentication via a certificate. This allows for potential attackers to create URLs that appear valid but return malicious responses to requests made by the app.

Prerequisites for Using Android MiTM Prevention:

To use Appdome’s mobile app security build system to Block Non-SSL Connections , you’ll need:

Block Non-SSL Connections on Android apps using Appdome

On Appdome, follow these 3 simple steps to create self-defending Android Apps that Block Non-SSL Connections 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. Android MiTM Prevention Compatible With: Java, JS, C++, C#, Kotlin, Flutter, React Native, Unity, Xamarin, Cordova and other Android apps
  2. Build the feature: Android MiTM Prevention.

    1. Building Android MiTM Prevention by using Appdome’s DEV-API:

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

        Figure 1: Fusion Set that will contain the Android MiTM Prevention 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 Android MiTM Prevention feature via Appdome Console, to add the Android MiTM Prevention 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, as shown in Figure 1 above, and get 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, 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 Android MiTM Prevention feature via Appdome Console

      To build the Android MiTM Prevention protection by using Appdome Console, follow the instructions below.

      1. Where: Inside the Appdome Console, go to Build > Security Tab > Secure Communication section.
      2. When you select the Android MiTM Prevention you'll notice that your Fusion Set you created in step 2.1.1 now bears the icon of the protection category that contains Android MiTM Prevention

        Fusion Set applied Android MiTM Prevention

        Figure 4: Fusion Set that displays the newly added Android MiTM Prevention protection

      3. Select the Threat-Event™ in-app mobile Threat Defense and Intelligence policy for Android MiTM Prevention:
        1. Threat-Events™ OFF > In-App Defense

          If the Threat-Events™ setting is cleared (not selected). Appdome will detect and defend the user and app by enforcing Block Non-SSL Connections.

        2. Threat-Events™ ON > In-App Detection

          When this setting is used, Appdome detects a non-secure connection (connection over HTTP) and passes Appdome’s Threat-Event™ attack intelligence to the app’s business logic for processing, enforcement, and user notification. For more information on consuming and using Appdome Threat-Events™ in the app, see section Using Threat-Events™ for Android MiTM Prevention Intelligence and Control in Mobile Apps.

        3. Threat-Events™ ON > In-App Defense

          When this setting is used, Appdome detects and defends against Non-SSL Connections (same as Appdome Enforce) and passes Appdome’s Threat-Event™ attack intelligence the app’s business logic for processing. For more information on consuming and using Appdome Threat-Events™ in the app, see section Using Threat-Events™ for Android MiTM Prevention Intelligence and Control in Mobile Apps.

      4. Click Build My App at the bottom of the Build Workflow (shown in Figure 3).
    Congratulations!  The Android MiTM Prevention protection is now added to the mobile app

Using Threat-Events™ for Non-SSL Connections Intelligence and Control in Android Apps

Appdome Threat-Events™ provides consumable in-app mobile app attack intelligence and defense control when Non-SSL Connections is detected. To consume and use Threat-Events™ for Non-SSL Connections in Android Apps, use registerReceiver in the Application OnCreate, and the code samples for Threat-Events™ for Non-SSL Connections shown below.

The specifications and options for Threat-Events™ for Non-SSL Connections are:

Threat-Event™ Elements Block Non-SSL Connections Method Detail
Appdome Feature Name Android MiTM Prevention
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
Visible in ThreatScope™
Developer Parameters for Blocking Non-SSL Connections Threat-Event™
Threat-Event NAME SslNonSslConnection
Threat-Event DATA reasonData
Threat-Event CODE reasonCode
Threat-Event REF 6801
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
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
deviceID Current device ID
reasonCode Reason code of the occured event
buildDate Appdome fusion date of the current application
devicePlatform OS name of the current device
carrierName Carrier name of the current device
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
host The host identified using non-TLS connections
DeveventDetailedErrorMessage Error message
extendedMessageText Extended message

With Threat-Events™ enabled (turned ON), Android developers can get detailed attack intelligence and granular defense control in Android applications and create amazing user experiences for all mobile end users when Non-SSL Connections is detected.

The following is a code sample for native Android apps, which uses all values in the specification above for Android MiTM Prevention:


Using Appdome, there are no development or coding prerequisites to build secured Android Apps by using Android MiTM Prevention. 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 Android MiTM Prevention

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:

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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