How to Detect MiTM Proxies, Prevent MiTM Attacks in Android & iOS Apps

Last updated March 16, 2023 by Appdome

Learn to Detect Malicious Proxies in Mobile apps, in mobile CI/CD with a Data-Driven DevSecOps™ build system.

What are Malicious Proxies?

Malicious proxies are proxy servers that are often used by malicious agents in mobile Man in the Middle (MiTM) attacks.

Hackers target insecure networks and Wi-Fi connections and hijack the connection between a mobile app and the server to which the app tries to connect. They then redirect the session to malicious proxies so they can perform malevolent actions such as harvesting data, stealing credentials, and depositing malware.

How does Appdome prevent the use of malicious proxy servers?

When the Malicious Proxy Detection is enabled, Appdome detects any attempt to connect to or from unknown, untrusted, or malicious proxies or other intermediary devices.

Detecting Malicious Proxies on Mobile apps by Using Appdome

On Appdome, follow these simple steps to create self-defending Mobile Apps that Detect Malicious Proxies without an SDK or gateway:

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
Build the feature: Malicious Proxy Detection.
1. Building Malicious Proxy Detection by using Appdome’s DEV-API:
  1. Create and name the Fusion Set (security template) that will contain the Malicious Proxy Detection feature as shown below:
  2. Follow the steps in Sections 2.2.1-2.2.2 of this article, Building the Malicious Proxy Detection feature via Appdome Console, to add the Malicious Proxy Detection 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:
    
    Build an API for the app – for instructions, see the tasks under Appdome API Reference Guide
    
    Look for sample APIs in Appdome’s GitHub Repository
2. Building the Malicious Proxy Detection feature via Appdome Console
  
  To build the Malicious Proxy Detection protection by using Appdome Console, follow the instructions below.
  1. Where: Inside the Appdome Console, go to Build > Security Tab > Secure Communication section
  2. How: Check whether Android MiTM Prevention is toggled On (enabled), otherwise enable it . You can see that the feature Malicious Proxy Detection is enabled by default, as shown below.
    
    Figure 3: Detect Malicious Proxies 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 enable 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 Malicious Proxy Detection
    
    Figure 4: Fusion Set that displays the newly added Malicious Proxy Detection protection
  4. Select the Threat-Event™ in-app mobile Threat Defense and Intelligence policy for Malicious Proxy Detection:
    
    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 Detect Malicious Proxies.
    
    Threat-Events™ ON > In-App Detection
    When this setting is used, Appdome detects malicious proxies 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 Malicious Proxy Detection Intelligence and Control in Mobile Apps.
    
    Threat-Events™ ON > In-App Defense
    When this setting is used, Appdome detects and defends against Malicious Proxies (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 Malicious Proxy Detection Intelligence and Control in Mobile Apps.
  5. Click Build My App at the bottom of the Build Workflow (shown in Figure 3).
Congratulations! The Malicious Proxy Detection protection is now added to the mobile app
Certify the Malicious Proxy Detection feature in Mobile Apps.

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

Using Threat-Events™ for Malicious Proxies Intelligence and Control in Mobile Apps

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

The specifications and options for Threat-Events™ for Malicious Proxies are:

Threat-Event™ Elements	Detect Malicious Proxies Method Detail
Appdome Feature Name	Malicious Proxy Detection
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 Detecting Malicious Proxies Threat-Event™
Threat-Event NAME	NetworkProxyConfigured
Threat-Event DATA	reasonData
Threat-Event CODE	reasonCode
Threat-Event REF	6510
Threat-Event SCORE
currentThreatEventScore	Current Threat-Event score
threatEventsScore	Total Threat-events score
Threat-Event Context Keys
blocked	was the keyboard blocked (True/False)
carrierPlmn	carrier identity number (PLMN code)
defaultMessage	the message that would be shown to the user in enforcement mode
deviceBrand	brand of the mobile device
deviceID	unique mobile installation identifier
deviceManufacturer	manufacturer of the mobile device
deviceModel	mobile device model
extendedMessageText	allows receiving extended metadata about threat events. Available only if the option
fusedAppToken	Appdome Built ID App Token
kernelInfo	Kernel information and details
Keyboard	package ID of the unauthorized keyboard to which the user tried to switch
osVersion	The mobile device OS version
sdkversion	Mobile SDK Version
timestamp	UNIX timestamp when event happened
OS Platform(s) Method	Mobile (registerReceiver)

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 Malicious Proxies is detected.

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

IntentFilter intentFilter = new IntentFilter();
                    intentFilter.addAction("NetworkProxyConfigured");
                    registerReceiver(new BroadcastReceiver() {
                            @Override
                            public void onReceive(Context context, Intent intent) {
                                String message = intent.getStringExtra("message"); // Message shown to the user
                                String reasonData = intent.getStringExtra("reasonData"); // Threat detection cause
                                String reasonCode = intent.getStringExtra("reasonCode"); // Event reason code
                                String currentThreatEventScore = intent.getStringExtra("currentThreatEventScore"); // Current threat event score
                                String threatEventsScore = intent.getStringExtra("threatEventsScore"); // Total threat events score
                                String variable = intent.getStringExtra("<Context Key>"); // Any other event specific context key

                                // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
                            }
                        }, intentFilter);

                        
                        Java
                    
​x
 
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("NetworkProxyConfigured");
registerReceiver(new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String message = intent.getStringExtra("message"); // Message shown to the user
            String reasonData = intent.getStringExtra("reasonData"); // Threat detection cause
            String reasonCode = intent.getStringExtra("reasonCode"); // Event reason code
            String currentThreatEventScore = intent.getStringExtra("currentThreatEventScore"); // Current threat event score
            String threatEventsScore = intent.getStringExtra("threatEventsScore"); // Total threat events score
            String variable = intent.getStringExtra("<Context Key>"); // Any other event specific context key
​
            // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
        }
    }, intentFilter);

val intentFilter = IntentFilter()
                intentFilter.addAction("NetworkProxyConfigured")
                registerReceiver(object : BroadcastReceiver() {
                    override fun onReceive(context: Context?, intent: Intent?) {
                        var message = intent.getStringExtra("message") // Message shown to the user
                        var reasonData = intent.getStringExtra("reasonData") // Threat detection cause
                        var reasonCode = intent.getStringExtra("reasonCode") // Event reason code
                        var currentThreatEventScore = intent.getStringExtra("currentThreatEventScore") // Current threat event score
                        var threatEventsScore = intent.getStringExtra("threatEventsScore") // Total threat events score
                        var variable = intent.getStringExtra("<Context Key>") // Any other event specific context key

                        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
                    }
                }, intentFilter)

                         
                        Kotlin
                    
​x
 
val intentFilter = IntentFilter()
intentFilter.addAction("NetworkProxyConfigured")
registerReceiver(object : BroadcastReceiver() {
    override fun onReceive(context: Context?, intent: Intent?) {
        var message = intent.getStringExtra("message") // Message shown to the user
        var reasonData = intent.getStringExtra("reasonData") // Threat detection cause
        var reasonCode = intent.getStringExtra("reasonCode") // Event reason code
        var currentThreatEventScore = intent.getStringExtra("currentThreatEventScore") // Current threat event score
        var threatEventsScore = intent.getStringExtra("threatEventsScore") // Total threat events score
        var variable = intent.getStringExtra("<Context Key>") // Any other event specific context key
​
        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
    }
}, intentFilter)

let center = NotificationCenter.default
                center.addObserver(forName: Notification.Name("NetworkProxyConfigured"), object: nil, queue: nil) { (note) in
                    guard let usrInf = note.userInfo else {
                        return
                    }

                    let message = usrInf["message"]; // Message shown to the user
                    let reasonData = usrInf["reasonData"]; // Threat detection cause
                    let reasonCode = usrInf["reasonCode"]; // Event reason code
                    let currentThreatEventScore = usrInf["currentThreatEventScore"]; // Current threat event score
                    let threatEventsScore = usrInf["threatEventsScore"]; // Total threat events score
                    let variable = usrInf["<Context Key>"]; // Any other event specific context key

                    // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
                }

                         
                        Swift
                    
​x
 
let center = NotificationCenter.default
center.addObserver(forName: Notification.Name("NetworkProxyConfigured"), object: nil, queue: nil) { (note) in
    guard let usrInf = note.userInfo else {
        return
    }
​
    let message = usrInf["message"]; // Message shown to the user
    let reasonData = usrInf["reasonData"]; // Threat detection cause
    let reasonCode = usrInf["reasonCode"]; // Event reason code
    let currentThreatEventScore = usrInf["currentThreatEventScore"]; // Current threat event score
    let threatEventsScore = usrInf["threatEventsScore"]; // Total threat events score
    let variable = usrInf["<Context Key>"]; // Any other event specific context key
​
    // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
}

[[NSNotificationCenter defaultCenter] addObserverForName:  @"NetworkProxyConfigured" object:nil queue:nil usingBlock:^(NSNotification *org_note) {
                    __block NSNotification *note = org_note;
                    dispatch_async(dispatch_get_main_queue(), ^(void) {
                        var threatEventsScore = intent.getStringExtra("threatEventsScore") 
                        NSString *message = [[note userInfo] objectForKey:@"message"]; // Message shown to the user
                        NSString *reasonData = [[note userInfo] objectForKey:@"reasonData"]; // Threat detection cause
                        NSString *reasonCode = [[note userInfo] objectForKey:@"reasonCode"]; // Event reason code
                        NSString *currentThreatEventScore = [[note userInfo] objectForKey:@"currentThreatEventScore"]; // Current threat event score
                        NSString *threatEventsScore = [[note userInfo] objectForKey:@"threatEventsScore"]; // Total threat events score
                        NSString *variable = [[note userInfo] objectForKey:@"<Context Key>"]; // Any other event specific context key

                        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
                    });
                }];

                         
                        Native iOS
                    
​x
 
[[NSNotificationCenter defaultCenter] addObserverForName:  @"NetworkProxyConfigured" object:nil queue:nil usingBlock:^(NSNotification *org_note) {
    __block NSNotification *note = org_note;
    dispatch_async(dispatch_get_main_queue(), ^(void) {
        var threatEventsScore = intent.getStringExtra("threatEventsScore") 
        NSString *message = [[note userInfo] objectForKey:@"message"]; // Message shown to the user
        NSString *reasonData = [[note userInfo] objectForKey:@"reasonData"]; // Threat detection cause
        NSString *reasonCode = [[note userInfo] objectForKey:@"reasonCode"]; // Event reason code
        NSString *currentThreatEventScore = [[note userInfo] objectForKey:@"currentThreatEventScore"]; // Current threat event score
        NSString *threatEventsScore = [[note userInfo] objectForKey:@"threatEventsScore"]; // Total threat events score
        NSString *variable = [[note userInfo] objectForKey:@"<Context Key>"]; // Any other event specific context key
​
        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
    });
}];

const { ADDevEvents } = NativeModules;
                const aDDevEvents = new NativeEventEmitter(ADDevEvents);

                function registerToDevEvent(action, callback) {
                    NativeModules.ADDevEvents.registerForDevEvent(action);
                    aDDevEvents.addListener(action, callback);
                }

                export function registerToAllEvents() {
                    registerToDevEvent(
                        "NetworkProxyConfigured",
                        (userinfo) => Alert.alert(JSON.stringify(userinfo))

                        var message = userinfo["message"] // Message shown to the user
                        var reasonData = userinfo["reasonData"] // Threat detection cause
                        var reasonCode = userinfo["reasonCode"] // Event reason code
                        var currentThreatEventScore = userinfo["currentThreatEventScore"] // Current threat event score
                        var threatEventsScore = userinfo["threatEventsScore"] // Total threat events score
                        var variable = userinfo["<Context Key>"] // Any other event specific context key

                        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
                    );
                }

                     
                    React Native
                
​x
 
const { ADDevEvents } = NativeModules;
const aDDevEvents = new NativeEventEmitter(ADDevEvents);
​
function registerToDevEvent(action, callback) {
    NativeModules.ADDevEvents.registerForDevEvent(action);
    aDDevEvents.addListener(action, callback);
}
​
export function registerToAllEvents() {
    registerToDevEvent(
        "NetworkProxyConfigured",
        (userinfo) => Alert.alert(JSON.stringify(userinfo))
​
        var message = userinfo["message"] // Message shown to the user
        var reasonData = userinfo["reasonData"] // Threat detection cause
        var reasonCode = userinfo["reasonCode"] // Event reason code
        var currentThreatEventScore = userinfo["currentThreatEventScore"] // Current threat event score
        var threatEventsScore = userinfo["threatEventsScore"] // Total threat events score
        var variable = userinfo["<Context Key>"] // Any other event specific context key
​
        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
    );
}
​

RegisterReceiver(new ThreatEventReceiver(), new IntentFilter("NetworkProxyConfigured"));
                class ThreatEventReceiver : BroadcastReceiver
                {
                public override void OnReceive(Context context, Intent intent)
                {
                    String message = intent.getStringExtra("message"); // Message shown to the user
                    String reasonData = intent.getStringExtra("reasonData"); // Threat detection cause
                    String reasonCode = intent.getStringExtra("reasonCode"); // Event reason code
                    String currentThreatEventScore = intent.getStringExtra("currentThreatEventScore"); // Current threat event score
                    String threatEventsScore = intent.getStringExtra("threatEventsScore"); // Total threat events score
                    String variable = intent.getStringExtra("<Context Key>"); // Any other event specific context key

                    // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
                }
                }

                    
                    Xamarin
                
​x
 
RegisterReceiver(new ThreatEventReceiver(), new IntentFilter("NetworkProxyConfigured"));
​
class ThreatEventReceiver : BroadcastReceiver
{
  public override void OnReceive(Context context, Intent intent)
  {
    String message = intent.getStringExtra("message"); // Message shown to the user
    String reasonData = intent.getStringExtra("reasonData"); // Threat detection cause
    String reasonCode = intent.getStringExtra("reasonCode"); // Event reason code
    String currentThreatEventScore = intent.getStringExtra("currentThreatEventScore"); // Current threat event score
    String threatEventsScore = intent.getStringExtra("threatEventsScore"); // Total threat events score
    String variable = intent.getStringExtra("<Context Key>"); // Any other event specific context key
​
    // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
  }
}

window.broadcaster.addEventListener("NetworkProxyConfigured", function(userInfo) {
        var message = userInfo.message // Message shown to the user
        var reasonData = userInfo.reasonData // Threat detection cause
        var reasonCode = userInfo.reasonCode // Event reason code
        var currentThreatEventScore = userInfo.currentThreatEventScore // Current threat event score
        var threatEventsScore = userInfo.threatEventsScore // Total threat events score
        var variable = userInfo.<Context Key> // Any other event specific context key

        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
            });

                    
                    Cordova
                
​x
 
window.broadcaster.addEventListener("NetworkProxyConfigured", function(userInfo) {
        var message = userInfo.message // Message shown to the user
        var reasonData = userInfo.reasonData // Threat detection cause
        var reasonCode = userInfo.reasonCode // Event reason code
        var currentThreatEventScore = userInfo.currentThreatEventScore // Current threat event score
        var threatEventsScore = userInfo.threatEventsScore // Total threat events score
        var variable = userInfo.<Context Key> // Any other event specific context key
​
        // Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
});

Prerequisites to Using Malicious Proxy Detection:

To use Appdome’s mobile app security build system to Detect Malicious Proxies , you’ll need:

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

Using Appdome, there are no development or coding prerequisites to build secured Mobile Apps by using Malicious Proxy Detection. 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 Malicious Proxy Detection

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:

Customizing, Configuring & Branding Secure Mobile Apps
Deploying/Publishing Secure mobile apps to Public or Private app stores
Releasing Secured Android & iOS Apps built on Appdome.

All apps protected by Appdome are fully compatible with any public app store, including Apple App Store, Google Play, Huawei App Gallery and more.

Features Similar to Malicious Proxy Detection

Here are a few related resources:

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.

How to Detect MiTM Proxies, Prevent MiTM Attacks in Android & iOS Apps

What are Malicious Proxies?

How does Appdome prevent the use of malicious proxy servers?

Detecting Malicious Proxies on Mobile apps by Using Appdome

Upload the Mobile App to Appdome.

Upload an app to Appdome’s Mobile App Security Build System

Build the feature: Malicious Proxy Detection.

Building Malicious Proxy Detection by using Appdome’s DEV-API:

Building the Malicious Proxy Detection feature via Appdome Console

Certify the Malicious Proxy Detection feature in Mobile Apps.

Using Threat-Events™ for Malicious Proxies Intelligence and Control in Mobile Apps

Prerequisites to Using Malicious Proxy Detection:

Thank you!