Trust Anchor not found for Android SSL Connection

You can trust particular certificate at runtime.
Just download it from server, put in assets and load like this using ssl-utils-android:

OkHttpClient client = new OkHttpClient();
SSLContext sslContext = SslUtils.getSslContextForCertificateFile(context, "BPClass2RootCA-sha2.cer");
client.setSslSocketFactory(sslContext.getSocketFactory());

In the example above I used OkHttpClient but SSLContext can be used with any client in Java.

If you have any questions feel free to ask. I'm the author of this small library.

If you use retrofit, you need to customize your OkHttpClient.

retrofit = new Retrofit.Builder()
    .baseUrl(ApplicationData.FINAL_URL)
    .client(getUnsafeOkHttpClient().build())
    .addConverterFactory(GsonConverterFactory.create())
    .build();

Full code are as below.

public class RestAdapter {

    private static Retrofit retrofit = null;
    private static ApiInterface apiInterface;

    public static OkHttpClient.Builder getUnsafeOkHttpClient() {
        try {
            // Create a trust manager that does not validate certificate chains
            final TrustManager[] trustAllCerts = new TrustManager[]{
                new X509TrustManager() {
                    @Override
                    public void checkClientTrusted(java.security.cert.X509Certificate[] chain, String authType) throws CertificateException {
                    }

                    @Override
                    public void checkServerTrusted(java.security.cert.X509Certificate[] chain, String authType) throws CertificateException {
                    }

                    @Override
                    public java.security.cert.X509Certificate[] getAcceptedIssuers() {
                        return new java.security.cert.X509Certificate[]{};
                    }
                }
            };
    
                // Install the all-trusting trust manager
                final SSLContext sslContext = SSLContext.getInstance("SSL");
                sslContext.init(null, trustAllCerts, new java.security.SecureRandom());
    
                // Create an ssl socket factory with our all-trusting manager
                final SSLSocketFactory sslSocketFactory = sslContext.getSocketFactory();
    
                OkHttpClient.Builder builder = new OkHttpClient.Builder();
                builder.sslSocketFactory(sslSocketFactory, (X509TrustManager) trustAllCerts[0]);
                builder.hostnameVerifier(new HostnameVerifier() {
                    @Override
                    public boolean verify(String hostname, SSLSession session) {
                        return true;
                    }
                });
                return builder;
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
        
        public static ApiInterface getApiClient() {
            if (apiInterface == null) {
    
                try {
                    retrofit = new Retrofit.Builder()
                            .baseUrl(ApplicationData.FINAL_URL)
                            .client(getUnsafeOkHttpClient().build())
                            .addConverterFactory(GsonConverterFactory.create())
                            .build();
    
                } catch (Exception e) {
    
                    e.printStackTrace();
                }
    
    
                apiInterface = retrofit.create(ApiInterface.class);
            }
            return apiInterface;
        }
        
    }

Use https://www.ssllabs.com/ssltest/ to test a domain.

The solution of Shihab Uddin in Kotlin.

import java.security.SecureRandom
import java.security.cert.X509Certificate
import javax.net.ssl.*
import javax.security.cert.CertificateException

object {

    val okHttpClient: OkHttpClient
    val gson: Gson
    val retrofit: Retrofit

    init {

        okHttpClient = getOkHttpBuilder()
            // Other parameters like connectTimeout(15, TimeUnit.SECONDS)
            .build()

        gson = GsonBuilder().setLenient().create()

        retrofit = Retrofit.Builder()
            .baseUrl(BASE_URL)
            .client(okHttpClient)
            .addConverterFactory(GsonConverterFactory.create(gson))
            .build()
    }

    fun getOkHttpBuilder(): OkHttpClient.Builder =
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            OkHttpClient().newBuilder()
        } else {
            // Workaround for the error "Caused by: com.android.org.bouncycastle.jce.exception.ExtCertPathValidatorException: Could not validate certificate: Certificate expired at".
            getUnsafeOkHttpClient()
        }

    private fun getUnsafeOkHttpClient(): OkHttpClient.Builder =
        try {
            // Create a trust manager that does not validate certificate chains
            val trustAllCerts: Array<TrustManager> = arrayOf(
                object : X509TrustManager {
                    @Throws(CertificateException::class)
                    override fun checkClientTrusted(chain: Array<X509Certificate?>?,
                                                    authType: String?) = Unit

                    @Throws(CertificateException::class)
                    override fun checkServerTrusted(chain: Array<X509Certificate?>?,
                                                    authType: String?) = Unit

                    override fun getAcceptedIssuers(): Array<X509Certificate> = arrayOf()
                }
            )
            // Install the all-trusting trust manager
            val sslContext: SSLContext = SSLContext.getInstance("SSL")
            sslContext.init(null, trustAllCerts, SecureRandom())
            // Create an ssl socket factory with our all-trusting manager
            val sslSocketFactory: SSLSocketFactory = sslContext.socketFactory
            val builder = OkHttpClient.Builder()
            builder.sslSocketFactory(sslSocketFactory,
                trustAllCerts[0] as X509TrustManager)
            builder.hostnameVerifier { _, _ -> true }
            builder
        } catch (e: Exception) {
            throw RuntimeException(e)
        }
}

The same error will also appear if you use Glide, images won't show. To overcome it see Glide - javax.net.ssl.SSLHandshakeException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found and How to set OkHttpClient for glide.

@GlideModule
class MyAppGlideModule : AppGlideModule() {

    val okHttpClient = Api.getOkHttpBuilder().build() // Api is the class written above.
    // It is better to create okHttpClient here and not use Api.okHttpClient,
    // because their settings may differ. For instance, it can use its own
    // `addInterceptor` and `addNetworkInterceptor` that can affect on a read JSON.


    override fun registerComponents(context: Context, glide: Glide, registry: Registry) {
        registry.replace(GlideUrl::class.java, InputStream::class.java,
            OkHttpUrlLoader.Factory(okHttpClient))
    }
}

build.gradle:

// Glide.
implementation 'com.github.bumptech.glide:glide:4.11.0'
implementation 'com.github.bumptech.glide:okhttp3-integration:4.11.0'
kapt 'com.github.bumptech.glide:compiler:4.11.0'

UPDATE

I also got another error on API 16 emulator:

routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version (external/openssl/ssl/s23_clnt.c:741'.

Reading 1 and 2, I changed code so:

okHttpClient = getOkHttpBuilder().build()

private fun getOkHttpBuilder(): OkHttpClient.Builder {
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
        Security.insertProviderAt(Conscrypt.newProvider(), 1)
    }
    return OkHttpClient().newBuilder()
}

// build.gradle:
implementation 'org.conscrypt:conscrypt-android:2.5.1'

I also removed these lines from MyApplication:

try {
    ProviderInstaller.installIfNeeded(applicationContext)
    val sslContext = SSLContext.getInstance("TLSv1.2")
    sslContext.init(null, null, null)
    sslContext.createSSLEngine()
} catch (e: GooglePlayServicesRepairableException) {
    Timber.e(e.stackTraceToString())
    // Prompt the user to install/update/enable Google Play services.
    GoogleApiAvailability.getInstance().showErrorNotification(this, e.connectionStatusCode)
} catch (e: GooglePlayServicesNotAvailableException) {
    Timber.e(e.stackTraceToString())
    // Prompt the user to install/update/enable Google Play services.
    // GoogleApiAvailability.getInstance().showErrorNotification(this, e.errorCode)
} catch (e: NoSuchAlgorithmException) {
    Timber.e(e.stackTraceToString())
} catch (e: KeyManagementException) {
    Timber.e(e.stackTraceToString())
}

But the library adds 3.4 Mb to apk.

I had the same problem while connecting from Android client to Kurento server. Kurento server use jks certificates, so I had to convert pem to it. As input for conversion I used cert.pem file and it lead to such errors. But if use fullchain.pem instead of cert.pem - all is OK.

I know that you don't need to trust all certificates but in my case I had problems with some debugging environments where we had self-signed certificates and I needed a dirty solution.

All I had to do was to change the initialization of the sslContext

mySSLContext.init(null, trustAllCerts, null); 

where trustAllCerts was created like this:

private final TrustManager[] trustAllCerts= new TrustManager[] { new X509TrustManager() {
    public java.security.cert.X509Certificate[] getAcceptedIssuers() {
        return new java.security.cert.X509Certificate[]{};
    }

    public void checkClientTrusted(X509Certificate[] chain,
                                   String authType) throws CertificateException {
    }

    public void checkServerTrusted(X509Certificate[] chain,
                                   String authType) throws CertificateException {
    }
} };

Hope that this will come in handy.

In my case, the root & intermediate certificates was successfully installed but I still got "Trust anchor for certification path not found." exception!. After digging the android document, found out that by default, secure connections (using protocols like TLS and HTTPS) from all apps trust the pre-installed system CAs, and apps targeting Android 6.0 (API level 23) and lower also trust the user-added CA store by default. If your app running on a OS with api level higher than 23 you should explicitly allow the app to trust user-added CA by adding its address to network_security_config like bellow:

<domain-config>
        <domain includeSubdomains="true">PUT_YOUR_SERVER_ADDERESS</domain>
        <trust-anchors>
            <certificates src="user" />
        </trust-anchors>
</domain-config>

The Trust anchor error can happen for a lot of reasons. For me it was simply that I was trying to access https://example.com/ instead of https://www.example.com/.

So you might want to double-check your URLs before starting to build your own Trust Manager (like I did).

I know this is a very old article, but I came across this article when trying to solve my trust anchor issues. I have posted how I fixed it. If you have pre-installed your Root CA you need to add a configuration to the manifest.

https://stackoverflow.com/a/60102517/114265

I have had a similar problem and I have completely ruled out the strategy of trusting all sources.

I share here my solution applied to an application implemented in Kotlin

I would first recommend using the following website to obtain information about the certificate and its validity

If it does not appear as an 'Accepted Issuers' in the Android default trust store, we must get that certificate and incorporate it into the application to create a custom trust store

The ideal solution in my case was to create a high-level Trust Manager that combines the custom and the Android default trust store

Here he exposes the high level code used to configure the OkHttpClient that he used with Retrofit.

override fun onBuildHttpClient(httpClientBuild: OkHttpClient.Builder) {

        val trustManagerWrapper = createX509TrustManagerWrapper(
            arrayOf(
                getCustomX509TrustManager(),
                getDefaultX509TrustManager()
            )
        )

        printX509TrustManagerAcceptedIssuers(trustManagerWrapper)

        val sslSocketFactory = createSocketFactory(trustManagerWrapper)
        httpClientBuild.sslSocketFactory(sslSocketFactory, trustManagerWrapper)

    }

In this way, I could communicate with the server with a self-signed certificate and with other servers with a certificate issued by a trusted certification entity

This is it, I hope it can help someone.

Sometimes it happens when admins setup the certificate incorrectly Check URL here https://www.sslshopper.com/ssl-checker.html

In my case, there was an error

The certificate is not trusted in all web browsers. You may need to install an Intermediate/chain certificate to link it to a trusted root certificate. Learn more about this error. You can fix this by following GlobalSign's Certificate Installation Instructions for your server platform. Pay attention to the parts about Intermediate certificates.

I use these methods that one of them is in solutions above works for me : First:

   public  okhttp3.OkHttpClient getUnsafeOkHttpClient() {
    try {
        // Create a trust manager that does not validate 
   certificate chains
        final TrustManager[] trustAllCerts = new TrustManager[] {
                new X509TrustManager() {
                    @Override
                    public void 
   checkClientTrusted(java.security.cert.X509Certificate[] chain, 
   String authType) throws CertificateException {
                    }

                    @Override
                    public void 
  checkServerTrusted(java.security.cert.X509Certificate[] chain, 
  String authType) throws CertificateException {
                    }

                    @Override
                    public java.security.cert.X509Certificate[] 
   getAcceptedIssuers() {
                        return new 
  java.security.cert.X509Certificate[]{};
                    }
                }
        };

        // Install the all-trusting trust manager
        final SSLContext sslContext = 
  SSLContext.getInstance("SSL");
        sslContext.init(null, trustAllCerts, new 
  java.security.SecureRandom());

        // Create an ssl socket factory with our all-trusting 
       manager
        final SSLSocketFactory sslSocketFactory = 
       sslContext.getSocketFactory();

        okhttp3.OkHttpClient.Builder builder = new 
      okhttp3.OkHttpClient.Builder();
        builder.sslSocketFactory(sslSocketFactory, 
      (X509TrustManager)trustAllCerts[0]);
        builder.hostnameVerifier(new HostnameVerifier() {
            @Override
            public boolean verify(String hostname, SSLSession 
       session) {
                return true;
            }
        });

        okhttp3.OkHttpClient okHttpClient = builder.build();
        return okHttpClient;
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}

Second:

    @SuppressLint("TrulyRandom")
    public static void handleSSLHandshake() {
    try {
        TrustManager[] trustAllCerts = new TrustManager[]{new 
       X509TrustManager() {
            public X509Certificate[] getAcceptedIssuers() {
                return new X509Certificate[0];
            }

            @Override
            public void checkClientTrusted(X509Certificate[] 
        certs, String authType) {
            }

            @Override
            public void checkServerTrusted(X509Certificate[] 
       certs, String authType) {
            }
        }};

        SSLContext sc = SSLContext.getInstance("SSL");
        sc.init(null, trustAllCerts, new SecureRandom());
        



  HttpsURLConnection
 .setDefaultSSLSocketFactory(sc.getSocketFactory());
        HttpsURLConnection.setDefaultHostnameVerifier(new 
    HostnameVerifier() {
            @Override
            public boolean verify(String arg0, SSLSession arg1) {
                return true;
            }
        });
    } catch (Exception ignored) {
    }
}

and: put this libraries to your classpath:

 implementation 'com.squareup.okhttp:okhttp:2.3.0'
implementation 'com.squareup.okhttp:okhttp-urlconnection:2.3.0'
    androidTestImplementation 'androidx.test.espresso:espresso- 
    core:3.3.0'

be sure that you call them in your class

Relpcae your clicent Like below var httpClient = new HttpClient(new System.Net.Http.HttpClientHandler());

Change https to http