How to resolve jsoup error: could not find a valid certification path for the requested target

Question

I am trying to parse the html of the following url:

https://www.smuc.ac.kr/mbs/smuc/jsp/board/list.jsp?boardId=6993&id=smuc_040100000000

I get the following error:

sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:387) at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292) at sun.security.validator.Validator.validate(Validator.java:260) at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324) at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229) at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124) at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1491) ... 15 more Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141) at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126) at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280) at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:382) ... 21 more 

This is my code:

 public class MainActivity extends AppCompatActivity { private ListView listView; private TextView textView; public ArrayList<String> arrayList = new ArrayList<String>(); private ArrayAdapter<String> arrayAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); listView = (ListView) findViewById(R.id.listView); new Insert().execute(); arrayAdapter = new ArrayAdapter<String>(MainActivity.this, R.layout.list_ok, R.id.text, arrayList ); } class Insert extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... params) { try { // Connection.Response res = Jsoup.connect("https://www.smuc.ac.kr/mbs/smuc/index.jsp") // .method(Connection.Method.POST) // .execute(); Document document = Jsoup.connect("https://www.smuc.ac.kr/mbs/smuc/jsp/board/list.jsp?boardId=6993&id=smuc_040100000000").get(); Elements elements = document.select(".tit"); arrayList.clear(); for (Element element : elements) { arrayList.add(element.text()); } } catch (IOException e) { e.printStackTrace(); } return null; } @Override protected void onPostExecute(String result){ listView.setAdapter(arrayAdapter); } } } 

Answer 1

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This answer is deprecated since JSoup is deprecated and removed the validateTLSCertificates method in version 1.12.1 ( https://jsoup.org/news/release-1.12.1 ).

You can ignore TSL validation, set validateTLSCertificates(false) :

 Document document = Jsoup.connect("URL").timeout(10000).validateTLSCertificates(false).get(); 

Since reading the page also takes some time, increase the timeout timeout(10000) .

Answer 2

The selected answer will not work with the latest releases of JSoup since validateTLSCertificates is deprecated and deleted. I created the following helper class:

 public class SSLHelper { static public Connection getConnection(String url){ return Jsoup.connect(url).sslSocketFactory(SSLHelper.socketFactory()); } static private SSLSocketFactory socketFactory() { TrustManager[] trustAllCerts = new TrustManager[]{new X509TrustManager() { public java.security.cert.X509Certificate[] getAcceptedIssuers() { return new X509Certificate[0]; } public void checkClientTrusted(X509Certificate[] certs, String authType) { } public void checkServerTrusted(X509Certificate[] certs, String authType) { } }}; try { SSLContext sslContext = SSLContext.getInstance("SSL"); sslContext.init(null, trustAllCerts, new java.security.SecureRandom()); SSLSocketFactory result = sslContext.getSocketFactory(); return result; } catch (NoSuchAlgorithmException | KeyManagementException e) { throw new RuntimeException("Failed to create a SSL socket factory", e); } } } 

Then I just call it like this:

Document doc = SSLHelper.getConnection (url) .userAgent (USER_AGENT) .get ();

(*) - https://dzone.com/articles/how-setup-custom - it is useful to come up with a solution