SafetyNet Safe Browsing API

The SafetyNet Safe Browsing API, a library powered by Google Play services, provides services for determining whether a URL has been marked as a known threat by Google.

Your app can use this API to determine whether a particular URL has been classified by Google as a known threat. Internally, SafetyNet implements a client for the Safe Browsing Network Protocol v4 developed by Google. Both the client code and the v4 network protocol were designed to preserve users' privacy and keep battery and bandwidth consumption to a minimum. Use this API to take full advantage of Google's Safe Browsing service on Android in the most resource-optimized way, and without implementing its network protocol.

The new version 5 (v5) update introduces significant improvements in data freshness and privacy through the use of Oblivious HTTP.

This document explains how to use the SafetyNet Safe Browsing Lookup API to check a URL for known threats.

Terms of service

By using the Safe Browsing API, you consent to be bound by the Terms of Service. Read and understand all applicable terms and policies before accessing the Safe Browsing API.

Request and register an Android API key

Before using the Safe Browsing API, create and register an Android API key. For specific steps, see the page about getting started with Safe Browsing.

In v5, you provide this API key when creating the SafeBrowsingClient instance.

Add the SafetyNet API dependency

Before using the Safe Browsing API, add the SafetyNet API to your project. If you are using Android Studio, add this dependency to your app-level Gradle file. For more information, see Protect against security threats with SafetyNet.

Initialize the API

To use the Safe Browsing API, you must initialize the API by calling initSafeBrowsing and waiting for it to complete. The following code snippet provides an example:

Kotlin

Tasks.await(SafetyNet.getClient(this).initSafeBrowsing)

Java

Tasks.await(SafetyNet.getClient(this).initSafeBrowsing);

In v5, GmsCore offers the Safe Browsing client. You must obtain a SafeBrowsingClient instance. We streamlined the API surface to increase efficiency and reduce bloat.

// Draft interface for the new client
public interface SafeBrowsingClient extends HasApiKey<SafeBrowsingApiOptions> {
  Task<SafeBrowsingResponse> lookupUri(String uri, @ThreatType List<Integer> threatTypes, @Protocol int protocol);
  Task<SupportedThreatTypesResponse> getSupportedThreatTypes();
}

Request a URL check

Use the lookupUri method to check if a URI poses a threat. You must specify the intended protocol, which can be either the local blocklist (v4) or real-time protection (v5) .

Send the URL check request

The API is independent to the scheme used, so you can pass the URL with or without a scheme. For example, both

Kotlin

var url = "https://www.google.com"

Java

String url = "https://www.google.com";

and

Kotlin

var url = "www.google.com"

Java

String url = "www.google.com";

are valid.

The following code demonstrates how to send a URL check request:

Kotlin

SafetyNet.getClient(this).lookupUri(
       url,
       SAFE_BROWSING_API_KEY,
       SafeBrowsingThreat.TYPE_POTENTIALLY_HARMFUL_APPLICATION,
       SafeBrowsingThreat.TYPE_SOCIAL_ENGINEERING
)
       .addOnSuccessListener(this) { sbResponse ->
           // Indicates communication with the service was successful.
           // Identify any detected threats.
           if (sbResponse.detectedThreats.isEmpty()) {
               // No threats found.
           } else {
               // Threats found!
           }
       }
       .addOnFailureListener(this) { e: Exception ->
           if (e is ApiException) {
               // An error with the Google Play services API contains some
               // additional details.
               Log.d(TAG, "Error: ${CommonStatusCodes.getStatusCodeString(e.statusCode)}")

               // Note: If the status code, s.statusCode,
               // is SafetyNetStatusCode.SAFE_BROWSING_API_NOT_INITIALIZED,
               // you need to call initSafeBrowsing(). It means either you
               // haven't called initSafeBrowsing() before or that it needs
               // to be called again due to an internal error.
           } else {
               // A different, unknown type of error occurred.
               Log.d(TAG, "Error: ${e.message}")
           }
       }

Java

SafetyNet.getClient(this).lookupUri(url,
         SAFE_BROWSING_API_KEY,
         SafeBrowsingThreat.TYPE_POTENTIALLY_HARMFUL_APPLICATION,
         SafeBrowsingThreat.TYPE_SOCIAL_ENGINEERING)
   .addOnSuccessListener(this,
       new OnSuccessListener<SafetyNetApi.SafeBrowsingResponse>() {
           @Override
           public void onSuccess(SafetyNetApi.SafeBrowsingResponse sbResponse) {
               // Indicates communication with the service was successful.
               // Identify any detected threats.
               if (sbResponse.getDetectedThreats().isEmpty()) {
                   // No threats found.
               } else {
                   // Threats found!
               }
        }
   })
   .addOnFailureListener(this, new OnFailureListener() {
           @Override
           public void onFailure(@NonNull Exception e) {
               // An error occurred while communicating with the service.
               if (e instanceof ApiException) {
                   // An error with the Google Play services API contains some
                   // additional details.
                   ApiException apiException = (ApiException) e;
                   Log.d(TAG, "Error: " + CommonStatusCodes
                       .getStatusCodeString(apiException.getStatusCode()));

                   // Note: If the status code, apiException.getStatusCode(),
                   // is SafetyNetStatusCode.SAFE_BROWSING_API_NOT_INITIALIZED,
                   // you need to call initSafeBrowsing(). It means either you
                   // haven't called initSafeBrowsing() before or that it needs
                   // to be called again due to an internal error.
               } else {
                   // A different, unknown type of error occurred.
                   Log.d(TAG, "Error: " + e.getMessage());
               }
           }
   });

The updated lookupUri signature takes the URI, a list of threat types, and the protocol.

val threatTypes = listOf(ThreatType.TYPE_SOCIAL_ENGINEERING, ThreatType.TYPE_MALWARE)
val protocol = Protocol.REAL_TIME // or Protocol.LOCAL_BLOCK_LIST

safeBrowsingClient.lookupUri(url, threatTypes, protocol)
    .addOnSuccessListener { response ->
        if (response.detectedThreats.isEmpty()) {
            // No threats found
        } else {
            // Threats detected!
        }
    }

Read the URL check response

Using the returned SafetyNetApi.SafeBrowsingResponse object, call its getDetectedThreats method, which returns a list of SafeBrowsingThreat objects. If the returned list is empty, the API didn't detect any known threats. If the list is not empty, call getThreatType on each element in the list to determine which known threats the API detected.

To see suggested warning language, see the Safe Browsing API Developer's Guide.

Specify threat types of interest

The constants in the SafeBrowsingThreat class contain the currently supported threat types:

Threat type Definition
TYPE_POTENTIALLY_HARMFUL_APPLICATION This threat type identifies URLs of pages that are flagged as containing potentially harmful applications.
TYPE_SOCIAL_ENGINEERING This threat type identifies URLs of pages that are flagged as containing social engineering threats.

When using the API, you add threat type constants as arguments. You can add as many threat type constants as your app requires, but you can only use constants that aren't marked as deprecated.

Shut down your Safe Browsing session

If your app doesn't need to use the Safe Browsing API for a prolonged period, check all the necessary URLs within your app and then shut down your Safe Browsing session using the shutdownSafeBrowsing method:

Kotlin

SafetyNet.getClient(this).shutdownSafeBrowsing()

Java

SafetyNet.getClient(this).shutdownSafeBrowsing();

We recommend that you call shutdownSafeBrowsing in your activity's onPause method and that you call initSafeBrowsing in your activity's onResume method. However, make sure that initSafeBrowsing has finished executing before calling lookupUri By making sure that your session is always fresh, you reduce the possibility of internal errors in your app.

Real-time protection details

The v5 update introduces a real-time protection mode that circumvents data staleness issues (which could reach 20-50 minutes in v4). It shifts from an allow-by-default to a check-by-default protocol, enhancing protection against fast-propagating threats. In real-time mode, clients maintain a local database and a Global Cache of likely-benign sites to provide near-real-time protection with the freshest threat data.

Supported threat types

The API lets you choose which threat types are important for your needs. The v5 API supports a wider range of threat types:

Threat Type Constant Description
NO_THREAT No threat.
TYPE_MALWARE General malware threats.
TYPE_UNWANTED_SOFTWARE Unwanted software or applications.
TYPE_POTENTIALLY_HARMFUL_APPLICATION Apps that may harm the device or user.
TYPE_SOCIAL_ENGINEERING Phishing and other deceptive sites.
TYPE_TRICK_TO_BILL Pages that trick users into billing actions.
TYPE_BETTER_ADS_VIOLATION Sites violating better ads standards.
TYPE_MALWARE_OFFLINE Offline malware.
TYPE_ABUSIVE_EXPERIENCE_VIOLATION Violations that result in a bad experience for the user.
TYPE_HIGH_CONFIDENCE_ALLOW_LIST High confidence allow list

Data collected by the SafetyNet Safe Browsing API

The SafetyNet Safe Browsing API collects the following data automatically when it communicates with the Safe Browsing service on Android:

Data Description
App Activity Collects hash prefix of URLs after a local hash prefix match for purposes of detecting malicious URLs.

The SafetyNet Safe Browsing API collects the hash prefix of URLs for detecting malicious URLs. Version 5 implements Oblivious HTTP to further protect user data during these lookups.

While we aim to be as transparent as possible, you are solely responsible for deciding how to respond to Google Play's data safety section form regarding your app's user data collection, sharing, and security practices.