"PKIX path building failed" and "unable to find valid certification path to requested target"

Go to URL in your browser:

firefox - click on HTTPS certificate chain (the lock icon right next to URL address). Click "more info" > "security" > "show certificate" > "details" > "export..". Pickup the name and choose file type example.cer

chrome - click on site icon left to address in address bar, select "Certificate" -> "Details" -> "Export" and save in format "Der-encoded binary, single certificate".

Now you have file with keystore and you have to add it to your JVM. Determine location of cacerts files, eg. C:\Program Files (x86)\Java\jre1.6.0_22\lib\security\cacerts. Next import the example.cer file into cacerts in command line (may need administrator command prompt):

keytool -import -alias example -keystore "C:\Program Files (x86)\Java\jre1.6.0_22\lib\security\cacerts" -file example.cer

You will be asked for password which default is changeit

Restart your JVM/PC.

source: http://magicmonster.com/kb/prg/java/ssl/pkix_path_building_failed.html

---

After many hours trying to build cert files to get my Java 6 installation working with the new twitter cert's, I finally stumbled onto an incredibly simple solution buried in a comment in one of the message boards. Just copy the cacerts file from a Java 7 installation and overwrite the one in your Java 6 installation. Probably best to make a backup of the cacerts file first, but then you just copy the new one in and BOOM! it just works.

Note that I actually copied a Windows cacerts file onto a Linux installation and it worked just fine.

The file is located in jre/lib/security/cacerts in both the old and new Java jdk installations.

Hope this saves someone else hours of aggravation.

---

MY UI approach:

Download keystore explorer from here Open $JAVA_HOME/jre/lib/security/cacerts enter PW: changeit (Can be changeme on Mac) Import your .crt file

CMD-Line:

keytool -importcert -file jetty.crt -alias jetty -keystore $JAVA_HOME/jre/lib/security/cacerts enter PW: changeit (Can be changeme on Mac)

---

1. Check the certificate

Try to load the target URL in browser and view the site's certificate (usually it's accessible by the icon with the lock sign. It's on the left or right side of the browser's address bar) whether it's expired or untrusted by other reason.

2. Install latest versions of JRE and JDK

New versions usually come with the updated set of the trusted certificates.

Also if it's possible, uninstall old versions. This will make misconfiguration errors explicit.

3. Check your configuration:

Check where your JAVA_HOME environment variable points to.

Check which java version you use to run the program. In IntelliJ check: File -> Project Structure... -> Project Settings -> Project -> Project SDK: File -> Project Structure... -> Platform Settings -> SDKs

File -> Project Structure... -> Project Settings -> Project -> Project SDK:

File -> Project Structure... -> Platform Settings -> SDKs

4. Copy whole keystore from the new Java version

If you develop under the JDK other than the latest available - try to replace the %JAVA_HOME%/jre/lib/security/cacerts file with the new one from the latest installed JRE (make a backup copy first) as @jeremy-goodell suggests in his answer

5. Add certificate(s) to your keystore

If nothing above solves your problem use keytool to save certificate(s) to the Java's keystore:

keytool -trustcacerts -keystore "%JAVA_HOME%jre\lib\security\cacerts" -storepass changeit -importcert -alias <alias_name> -file <path_to_crt_file>

File with the certificate can be obtained from the browser as @MagGGG suggests in his answer.

Note 1: you may need to repeat this for every certificate in the chain to you site's certificate. Start from the root one.

Note 2: <alias_name> should be unique among the keys in the store or keytool will show an error.

To get list of all the certificates in the store you may run:

keytool -list -trustcacerts -keystore "%JAVA_HOME%jre\lib\security\cacerts" -storepass changeit

In case something goes wrong this will help you to remove certificate from the store:

keytool -delete -alias <alias_name> -keystore "%JAVA_HOME%jre\lib\security\cacerts" -storepass changeit

---

-Dmaven.wagon.http.ssl.insecure=true -Dmaven.wagon.http.ssl.allowall=true

It is used for jump the certificate validation.

Warning Only use for development purposes for this is unsecure!

---

I have stumbled upon this issue which took many hours of research to fix, specially with auto-generated certificates, which unlike Official ones, are quite tricky and Java does not like them that much.

Please check the following link: Solve Problem with certificates in Java

Basically you have to add the certificate from the server to the Java Home certs.

Generate or Get your certificate and configure Tomcat to use it in Servers.xml Download the Java source code of the class InstallCert and execute it while the server is running, providing the following arguments server[:port]. No password is needed, as the original password works for the Java certs ("changeit"). The Program will connect to the server and Java will throw an exception, it will analyze the certificate provided by the server and allow you to create a jssecerts file inside the directory where you executed the Program (If executed from Eclipse then make sure you configure the Work directory in Run -> Configurations). Manually copy that file to $JAVA_HOME/jre/lib/security

After following these steps, the connections with the certificate will not generate exceptions anymore within Java.

The following source code is important and it disappeared from (Sun) Oracle blogs, the only page I found it was on the link provided, therefore I am attaching it in the answer for any reference.

/*
 * Copyright 2006 Sun Microsystems, Inc.  All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/**
 * Originally from:
 * http://blogs.sun.com/andreas/resource/InstallCert.java
 * Use:
 * java InstallCert hostname
 * Example:
 *% java InstallCert ecc.fedora.redhat.com
 */

import javax.net.ssl.*;
import java.io.*;
import java.security.KeyStore;
import java.security.MessageDigest;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

/**
 * Class used to add the server's certificate to the KeyStore
 * with your trusted certificates.
 */
public class InstallCert {

    public static void main(String[] args) throws Exception {
        String host;
        int port;
        char[] passphrase;
        if ((args.length == 1) || (args.length == 2)) {
            String[] c = args[0].split(":");
            host = c[0];
            port = (c.length == 1) ? 443 : Integer.parseInt(c[1]);
            String p = (args.length == 1) ? "changeit" : args[1];
            passphrase = p.toCharArray();
        } else {
            System.out.println("Usage: java InstallCert [:port] [passphrase]");
            return;
        }

        File file = new File("jssecacerts");
        if (file.isFile() == false) {
            char SEP = File.separatorChar;
            File dir = new File(System.getProperty("java.home") + SEP
                    + "lib" + SEP + "security");
            file = new File(dir, "jssecacerts");
            if (file.isFile() == false) {
                file = new File(dir, "cacerts");
            }
        }
        System.out.println("Loading KeyStore " + file + "...");
        InputStream in = new FileInputStream(file);
        KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
        ks.load(in, passphrase);
        in.close();

        SSLContext context = SSLContext.getInstance("TLS");
        TrustManagerFactory tmf =
                TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
        tmf.init(ks);
        X509TrustManager defaultTrustManager = (X509TrustManager) tmf.getTrustManagers()[0];
        SavingTrustManager tm = new SavingTrustManager(defaultTrustManager);
        context.init(null, new TrustManager[]{tm}, null);
        SSLSocketFactory factory = context.getSocketFactory();

        System.out.println("Opening connection to " + host + ":" + port + "...");
        SSLSocket socket = (SSLSocket) factory.createSocket(host, port);
        socket.setSoTimeout(10000);
        try {
            System.out.println("Starting SSL handshake...");
            socket.startHandshake();
            socket.close();
            System.out.println();
            System.out.println("No errors, certificate is already trusted");
        } catch (SSLException e) {
            System.out.println();
            e.printStackTrace(System.out);
        }

        X509Certificate[] chain = tm.chain;
        if (chain == null) {
            System.out.println("Could not obtain server certificate chain");
            return;
        }

        BufferedReader reader =
                new BufferedReader(new InputStreamReader(System.in));

        System.out.println();
        System.out.println("Server sent " + chain.length + " certificate(s):");
        System.out.println();
        MessageDigest sha1 = MessageDigest.getInstance("SHA1");
        MessageDigest md5 = MessageDigest.getInstance("MD5");
        for (int i = 0; i < chain.length; i++) {
            X509Certificate cert = chain[i];
            System.out.println
                    (" " + (i + 1) + " Subject " + cert.getSubjectDN());
            System.out.println("   Issuer  " + cert.getIssuerDN());
            sha1.update(cert.getEncoded());
            System.out.println("   sha1    " + toHexString(sha1.digest()));
            md5.update(cert.getEncoded());
            System.out.println("   md5     " + toHexString(md5.digest()));
            System.out.println();
        }

        System.out.println("Enter certificate to add to trusted keystore or 'q' to quit: [1]");
        String line = reader.readLine().trim();
        int k;
        try {
            k = (line.length() == 0) ? 0 : Integer.parseInt(line) - 1;
        } catch (NumberFormatException e) {
            System.out.println("KeyStore not changed");
            return;
        }

        X509Certificate cert = chain[k];
        String alias = host + "-" + (k + 1);
        ks.setCertificateEntry(alias, cert);

        OutputStream out = new FileOutputStream("jssecacerts");
        ks.store(out, passphrase);
        out.close();

        System.out.println();
        System.out.println(cert);
        System.out.println();
        System.out.println
                ("Added certificate to keystore 'jssecacerts' using alias '"
                        + alias + "'");
    }

    private static final char[] HEXDIGITS = "0123456789abcdef".toCharArray();

    private static String toHexString(byte[] bytes) {
        StringBuilder sb = new StringBuilder(bytes.length * 3);
        for (int b : bytes) {
            b &= 0xff;
            sb.append(HEXDIGITS[b >> 4]);
            sb.append(HEXDIGITS[b & 15]);
            sb.append(' ');
        }
        return sb.toString();
    }

    private static class SavingTrustManager implements X509TrustManager {

        private final X509TrustManager tm;
        private X509Certificate[] chain;

        SavingTrustManager(X509TrustManager tm) {
            this.tm = tm;
        }

        public X509Certificate[] getAcceptedIssuers() {
            throw new UnsupportedOperationException();
        }

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

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

---

Mac

The accepted answer does not work for Mac as there is no Export button available in Mac (Chrome or Firefox). Please check this answer to download the certificate and follow the next steps as mentioned below:

List all certificates installed in the keystore:

cd $JAVA_HOME/lib/security
keytool -list -keystore cacerts

Notes:

The default password of the keystore is: changeit.

For Java-8 or lower version use the command, cd $JAVA_HOME/jre/lib/security

Before you import the certificate in the keystore, make a backup of the keystore:

sudo cp cacerts cacerts.bak

Import the downloaded certificate in the keystore:

sudo keytool -importcert -alias youralias -file /path/to/the/downloaded/certificate -keystore cacerts

Check if the certificate is stored in the keystore:

sudo keytool -list -keystore cacerts -alias youralias

If you want to see more detailed information, add the -v flag:

sudo keytool -v -list -keystore cacerts -alias youralias

---

I wanted to import certificate for smtp.gmail.com. The only solution that worked for me is

Enter command to view this certificate D:\openssl\bin\openssl.exe s_client -connect smtp.gmail.com:465 Copy and save the lines between -----BEGIN CERTIFICATE----- and -----END CERTIFICATE----- into a file, gmail.cer Run keytool -import -alias smtp.gmail.com -keystore "%JAVA_HOME%/jre/lib/security/cacerts" -file C:\Users\Admin\Desktop\gmail.cer Enter password: changeit Click "Yes" to import the certificate Restart Java

Now run the command and you are good to go.

---

I had a slightly different situation, when both JDK and JRE 1.8.0_112 were present on my system.

I imported the new CA certificates into [JDK_FOLDER]\jre\lib\security\cacerts using the already known command:

keytool -import -trustcacerts -keystore cacerts -alias <new_ca_alias> -file <path_to_ca_cert_file>

Still, I kept getting the same PKIX path building failed error.

I added debug information to the java CLI, by using java -Djavax.net.debug=all ... > debug.log. In the debug.log file, the line that begins with trustStore is: actually pointed to the cacerts store found in [JRE_FOLDER]\lib\security\cacerts.

In my case the solution was to copy the cacerts file used by JDK (which had the new CAs added) over the one used by the JRE and that fixed the issue.

---

This isn't a Twitter-specific answer, but this is the question that comes up when you search for this error. If your system is receiving this error when connecting to a website that appears to have a valid certificate when viewed in a web browser, that probably means that website has an incomplete certificate chain.

For a brief summary of the problem: Certificate Authorities don't use their Root Certificate to sign just any old certificate. Instead, they (usually) sign intermediate certificates that also have the Certificate Authority flag set (that is, are allowed to sign certificates). Then when you purchase a certificate from a CA, they sign your CSR with one of these intermediate certificates.

Your Java trust store most likely only has the Root Cert, not the intermediate ones.

A misconfigured site might return just their signed cert. Problem: it was signed with an intermediate cert that's not in your trust store. Browsers will handle this problem by downloading or using a cached intermediate certificate; this maximizes website compatibility. Java and tools like OpenSSL, however, won't. And that will cause the error in the question.

You can verify this suspicion by using the Qualys SSL Test. If you run that against a site and it says

This server's certificate chain is incomplete.

then that confirms it. You can also see this by looking at the certification paths and seeing the text Extra Download.

How to fix it: the server administrator needs to configure the web server to return the intermediate certificates as well. For Comodo, for example, this is where the .ca-bundle file comes in handy. For example, in an Apache configuration with mod_ssl, you'd use the SSLCertificateChainFile configuration setting. For nginx, you need to concatenate the intermediate certificates and the signed certificate and use that in the SSL cert configuration. You can find more by searching for "incomplete certificate chain" online.

---

Issue Background:

I was getting following error when i try to run mvn clean install in my project and through Netbeans IDE clean and build option. This issue is due to certificate not available when we download through NET beans IDE/through command prompt, but able to download the files through the browser.

Error:

Caused by: org.eclipse.aether.transfer.ArtifactTransferException: Could not transfer artifact com.java.project:product:jar:1.0.32 from/to repo-local (https://url/local-repo): sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target  

Resolution:

1. Download the certificate of the Url in question:

Launch IE by "run as adminstrator" (otherwise, we will not be able to download the certificate)

Enter the url in IE-> https://url/local-repo (In my case this url had a untrusted certificate.)

Download the certificate by clicking on Certificate error -> view certificate

Select Details tab -> copy to file -> next -> select "DER encoded binary X.509 (.CER)

save the certificate in some location, example : c:/user/sheldon/desktop/product.cer

Congrats! you have successfully downloaded the certificate for the site

2. Now install the key store to fix the issue.

Run the keytool command to append the downloaded keystore into the existing certificate file.

Command: Below command in the bin folder of jdk (JAVA_HOME).

C:\Program Files\Java\jdk1.8.0_141\jre\bin>keytool -importcert -file "C:/user/sheldon/desktop/product.cer" -alias product -keystore "C:/Program Files/Java/jdk1.8.0_141/jre/lib/security/cacerts".

You will be prompted to enter password. Enter keystore password: enter "changeit" again for "Trust this certificate? [no]:", enter "yes"

Sample command line commands/output:

keytool -importcert -file "C:/Users/sheldon/Desktop/product.cer" -alias product -keystore "C:/Program iles/Java/jdk1.8.0_141/jre/lib/security/cacerts"
Enter keystore password:
Trust this certificate? [no]:  yes
Certificate was added to keystore

Contgrats! now you should have got rid of "PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException" error in your Netbeans IDE.

---

This is a solution but in form of my story with this problem:

I was almost dead trying all the solution given above(for 3 days ) and nothing worked for me.

I lost all hope.

I contacted my security team regarding this because i was behind a proxy and they told that they had recently updated their security policy.

I scolded them badly for not informing the Developers.

Later they issued a new "cacerts" file which contains all the certificates.

I removed the cacerts file which is present inside %JAVA_HOME%/jre/lib/security and it solved my problem.

So if you are facing this issue it might be from your network team also like this.

---

The reason, we get above error is that JDK is bundled with a lot of trusted Certificate Authority(CA) certificates into a file called ‘cacerts’ but this file has no clue of our self-signed certificate. In other words, the cacerts file doesn’t have our self-signed certificate imported and thus doesn’t treat it as a trusted entity and hence it gives the above error.

How to fix the above error

To fix the above error, all we need is to import the self-signed certificate into the cacerts file.

First, locate the cacerts file. We will need to find out the JDK location. If you are running your application through one of the IDE’s like Eclipse or IntelliJ Idea go to project settings and figure out what is the JDK location. For e.g on a Mac OS typical location of cacerts file would be at this location /Library/Java/JavaVirtualMachines/ {{JDK_version}}/Contents/Home/jre/lib/security on a Window’s machine it would be under {{Installation_directory}}/{{JDK_version}}/jre/lib/security

Once you have located the cacerts file, now we need to import our self-signed certificate to this cacerts file. Check the last article, if you don’t know how to generate the self-signed certificate correctly.

If you don’t have a certificate file(.crt) and just have a .jks file you can generate a .crt file by using below command. In case you already have a .crt/.pem file then you can ignore below command

##To generate certificate from keystore(.jks file) ####

keytool -export -keystore keystore.jks -alias selfsigned -file selfsigned.crt

Above step will generate a file called selfsigned.crt.Now Import the certificate to cacerts

keytool -importcert -file selfsigned.crt -alias selfsigned -keystore {{cacerts path}}

for e.g

keytool -importcert -file selfsigned.nextgen.crt -alias selfsigned.nextgen -keystore /Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/security/cacerts

That’s all, restart your application and it should work fine. If it still doesn’t work and get an SSL handshake exception. It probably means you are using different domain then registered in the certificate.

The Link with detailed explanation and step by step resolution is over here.

---

After struggling for half-day, found one more way to solve this problem. I was able to solve this in MAC 10.15.5 ( Catalina). Followed the below steps.

This problem occurs when we are running behind a company proxy , In my case its Zscaler.

Open Key chain access, export CA certificate.(Select CA certificate, File->export items and save with the desired name)

Copy the path of existing cacerts from java folder(/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/security/cacerts )

Open terminal and navigate to the Keytool folder (/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/bin )

Run the below command.

Keytool -importcert - file (Path to exported cert from the keychainaccess) -alias (give a name) -keystore (Path of existing cacerts from java folder)

sudo Keytool -importcert -file /Users/Desktop/RootCA.cer -alias demo -keystore /Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre/lib/security/cacerts

It will ask for password , give it as : changeit

It asks for confirmation , Say : yes

After all of these steps, Quit eclipse and terminal start fresh session.

---

I was facing the same issue and get it resolved using the below simple steps:

1) Download the InstallCert.java from google

2) Compile it using javac InstallCert.java

3) Run InstallCert.java using java InstallCert.java, with the hostname and https port, and press “1” when asking for input. It will add the “localhost” as a trusted keystore, and generate a file named “jssecacerts“ as below:

java InstallCert localhost:443

4) copy the jssecacerts into $JAVA_HOME/jre/lib/security folder

Main source to resolve the issue here is:

https://ankurjain26.blogspot.in/2017/11/javaxnetsslsslhandshakeexception.html

---

Adding cacerts did not work for me. After enabling log with flag -Djavax.net.debug=all, then came to know java reading from jssecacerts.

Import to jssecacerts worked finally.

---

For me, certificate error popped up because I had fiddler running in background and that messes up with certificate. It acts as a proxy so close that and restart eclipse.

---

I came across this question while trying to install the Cucumber-Eclipse plugin in Eclipse via their update site. I received the same SunCertPathBuilderException error:

Unable to read repository at http://cucumber.io/cucumber-eclipse/update-site/content.xml.
    Unable to read repository at http://cucumber.io/cucumber-eclipse/update-site/content.xml.
    sun.security.validator.ValidatorException: PKIX path building failed: 
   sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

While some of the other answers are appropriate and helpful for this question's given situation, they were nevertheless unhelpful and misleading for my issue.

In my case, the issue was that the URL provided for their update site is:

https://cucumber.io/cucumber-eclipse/update-site

However when navigating to it via a browser, it redirected to (note the added ".github"):

http://cucumber.github.io/cucumber-eclipse/update-site/

So the resolution is to simply use the redirected version of the update site URL when adding the update site in eclipse.

---

I solved this issue on Windows Server 2016 with Java 8, by importing cert from pkcs12 store to cacerts keystore.

Path to pkcs12 store:
C:\Apps\pkcs12.pfx

Path to Java cacerts:
C:\Program Files\Java\jre1.8.0_151\lib\security\cacerts

Path to keytool:
C:\Program Files\Java\jre1.8.0_151\bin

After possitioning to folder with keytool in command prompt (as administrator), command to import cert from pkcs12 to cacerts is as follows:
keytool -v -importkeystore -srckeystore C:\Apps\pkcs12.pfx -srcstoretype PKCS12 -destkeystore "C:\Program Files\Java\jre1.8.0_151\lib\security\cacerts" -deststoretype JKS

You will be prompted to:
1. enter destination keystore password (cacerts pasword, default is "changeit")
2. enter source keystore password (pkcs12 password)

For changes to take effect, restart server machine (or just restart JVM).

---

Problem is, your eclipse is not able to connect the site which actually it is trying to. I have faced similar issue and below given solution worked for me.

Turn off any third party internet security application e.g. Zscaler Sometimes also need to disconnect VPN if you are connected.

Thanks

---

goals:

use https connections verify SSL chains do not deal with cacerts add certificate in runtime do not lose certificates from cacerts

How to do it:

define own keystore put certificate into keystore redefine SSL default context with our custom class ??? profit

My Keystore wrapper file:

public class CertificateManager {

    private final static Logger logger = Logger.getLogger(CertificateManager.class);

    private String keyStoreLocation;
    private String keyStorePassword;
    private X509TrustManager myTrustManager;
    private static KeyStore myTrustStore;

    public CertificateManager(String keyStoreLocation, String keyStorePassword) throws Exception {
        this.keyStoreLocation = keyStoreLocation;
        this.keyStorePassword = keyStorePassword;
        myTrustStore = createKeyStore(keyStoreLocation, keyStorePassword);
    }

    public void addCustomCertificate(String certFileName, String certificateAlias)
            throws Exception {
        TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
        tmf.init((KeyStore) null);
        Certificate certificate = myTrustStore.getCertificate(certificateAlias);
        if (certificate == null) {
            logger.info("Certificate not exists");
            addCertificate(certFileName, certificateAlias);
        } else {
            logger.info("Certificate exists");
        }
        tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
        tmf.init(myTrustStore);
        for (TrustManager tm : tmf.getTrustManagers()) {
            if (tm instanceof X509TrustManager) {
                setMytrustManager((X509TrustManager) tm);
                logger.info("Trust manager found");
                break;
            }
        }
    }

    private InputStream fullStream(String fname) throws IOException {
        ClassLoader classLoader = getClass().getClassLoader();
        InputStream resource = classLoader.getResourceAsStream(fname);
        try {
            if (resource != null) {
                DataInputStream dis = new DataInputStream(resource);
                byte[] bytes = new byte[dis.available()];
                dis.readFully(bytes);
                return new ByteArrayInputStream(bytes);
            } else {
                logger.info("resource not found");
            }
        } catch (Exception e) {
            logger.error("exception in certificate fetching as resource", e);
        }
        return null;
    }

    public static KeyStore createKeyStore(String keystore, String pass) throws Exception {
        try {
            InputStream in = CertificateManager.class.getClass().getResourceAsStream(keystore);
            KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
            keyStore.load(in, pass.toCharArray());
            logger.info("Keystore was created from resource file");
            return keyStore;
        } catch (Exception e) {
            logger.info("Fail to create keystore from resource file");
        }

        File file = new File(keystore);
        KeyStore keyStore = KeyStore.getInstance("JKS");
        if (file.exists()) {
            keyStore.load(new FileInputStream(file), pass.toCharArray());
            logger.info("Default keystore loaded");
        } else {
            keyStore.load(null, null);
            keyStore.store(new FileOutputStream(file), pass.toCharArray());
            logger.info("New keystore created");
        }
        return keyStore;
    }

    private void addCertificate(String certFileName, String certificateAlias) throws CertificateException,
            IOException, KeyStoreException, NoSuchAlgorithmException {
        CertificateFactory cf = CertificateFactory.getInstance("X.509");
        InputStream certStream = fullStream(certFileName);
        Certificate certs = cf.generateCertificate(certStream);
        myTrustStore.setCertificateEntry(certificateAlias, certs);
        FileOutputStream out = new FileOutputStream(getKeyStoreLocation());
        myTrustStore.store(out, getKeyStorePassword().toCharArray());
        out.close();
        logger.info("Certificate pushed");
    }

    public String getKeyStoreLocation() {
        return keyStoreLocation;
    }

    public String getKeyStorePassword() {
        return keyStorePassword;
    }
    public X509TrustManager getMytrustManager() {
        return myTrustManager;
    }
    public void setMytrustManager(X509TrustManager myTrustManager) {
        this.myTrustManager = myTrustManager;
    }
}

This class will create keystore if necessary, and will be able to manage certificates inside of it. Now class for SSL context:

public class CustomTrustManager implements X509TrustManager {

    private final static Logger logger = Logger.getLogger(CertificateManager.class);

    private static SSLSocketFactory socketFactory;
    private static CustomTrustManager instance = new CustomTrustManager();
    private static List<CertificateManager> register = new ArrayList<>();

    public static CustomTrustManager getInstance() {
        return instance;
    }

    private X509TrustManager defaultTm;

    public void register(CertificateManager certificateManager) {
        for(CertificateManager manager : register) {
            if(manager == certificateManager) {
                logger.info("Certificate manager already registered");
                return;
            }
        }
        register.add(certificateManager);
        logger.info("New Certificate manager registered");
    }

    private CustomTrustManager() {
        try {
            String algorithm = TrustManagerFactory.getDefaultAlgorithm();
            TrustManagerFactory tmf = TrustManagerFactory.getInstance(algorithm);

            tmf.init((KeyStore) null);
            boolean found = false;
            for (TrustManager tm : tmf.getTrustManagers()) {
                if (tm instanceof X509TrustManager) {
                    defaultTm = (X509TrustManager) tm;
                    found = true;
                    break;
                }
            }
            if(found) {
                logger.info("Default trust manager found");
            } else {
                logger.warn("Default trust manager was not found");
            }

            SSLContext sslContext = SSLContext.getInstance("TLS");
            sslContext.init(null, new TrustManager[]{this}, null);
            SSLContext.setDefault(sslContext);
            socketFactory = sslContext.getSocketFactory();
            HttpsURLConnection.setDefaultSSLSocketFactory(socketFactory);


            logger.info("Custom trust manager was set");
        } catch (NoSuchAlgorithmException | KeyManagementException | KeyStoreException e) {
            logger.warn("Custom trust manager can't be set");
            e.printStackTrace();
        }
    }

    @Override
    public X509Certificate[] getAcceptedIssuers() {
        List<X509Certificate> out = new ArrayList<>();
        if (defaultTm != null) {
            out.addAll(Arrays.asList(defaultTm.getAcceptedIssuers()));
        }
        int defaultCount = out.size();
        logger.info("Default trust manager contain " + defaultCount + " certficates");
        for(CertificateManager manager : register) {
            X509TrustManager customTrustManager = manager.getMytrustManager();
            X509Certificate[] issuers = customTrustManager.getAcceptedIssuers();
            out.addAll(Arrays.asList(issuers));
        }
        logger.info("Custom trust managers contain " + (out.size() - defaultCount) + " certficates");
        X509Certificate[] arrayOut = new X509Certificate[out.size()];
        return out.toArray(arrayOut);
    }

    @Override
    public void checkServerTrusted(X509Certificate[] chain,
                                   String authType) throws CertificateException {
        for(CertificateManager certificateManager : register) {
            X509TrustManager customTrustManager = certificateManager.getMytrustManager();
            try {
                customTrustManager.checkServerTrusted(chain, authType);
                logger.info("Certificate chain (server) was aproved by custom trust manager");
                return;
            } catch (Exception e) {
            }
        }
        if (defaultTm != null) {
            defaultTm.checkServerTrusted(chain, authType);
            logger.info("Certificate chain (server) was aproved by default trust manager");
        } else {
            logger.info("Certificate chain (server) was rejected");
            throw new CertificateException("Can't check server trusted certificate.");
        }
    }

    @Override
    public void checkClientTrusted(X509Certificate[] chain,
                                   String authType) throws CertificateException {
        try {
            if (defaultTm != null) {
                defaultTm.checkClientTrusted(chain, authType);
                logger.info("Certificate chain (client) was aproved by default trust manager");
            } else {
                throw new NullPointerException();
            }
        } catch (Exception e) {
            for(CertificateManager certificateManager : register) {
                X509TrustManager customTrustManager = certificateManager.getMytrustManager();
                try {
                    customTrustManager.checkClientTrusted(chain, authType);
                    logger.info("Certificate chain (client) was aproved by custom trust manager");
                    return;
                } catch (Exception e1) {
                }
            }
            logger.info("Certificate chain (client) was rejected");
            throw new CertificateException("Can't check client trusted certificate.");
        }
    }

    public SSLSocketFactory getSocketFactory() {
        return socketFactory;
    }
}

This class made as singleton, because only one defaultSSL context allowed. So, now usage:

            CertificateManager certificateManager = new CertificateManager("C:\\myapplication\\mykeystore.jks", "changeit");
            String certificatePath = "C:\\myapplication\\public_key_for_your_ssl_service.crt";
            try {
                certificateManager.addCustomCertificate(certificatePath, "alias_for_public_key_for_your_ssl_service");
            } catch (Exception e) {
                log.error("Can't add custom certificate");
                e.printStackTrace();
            }
            CustomTrustManager.getInstance().register(certificateManager);

Possibly, it will not work with this settings, because I keep certificate file inside of resource folder, so my path is not absolute. But generally, it work perfectly.

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If your repository URL also work on HTTP and the security is not a concern, you can go to settings.xml (often, but not always, located in %USERPROFILE%/.m2) and replace HTTPS with HTTP for <repository> and <pluginRepository> URLs.

For example, this:

<repository>
    <snapshots>
        <enabled>false</enabled>
    </snapshots>
    <id>central</id>
    <name>libs-release</name>
    <url>https://<artifactory>/libs-release</url>
</repository>

should be replaced by this:

<repository>
    <snapshots>
        <enabled>false</enabled>
    </snapshots>
    <id>central</id>
    <name>libs-release</name>
    <url>https://<artifactory>/libs-release</url>
</repository>

---

I was using my own trust store rather than JRE one by passing arg -Djavax.net.ssl.trustStore=

I was getting this error regardless of certs in truststore. The issue for me was the ordering of of the properties passed on arg line. When i put -Djavax.net.ssl.trustStore=& -Djavax.net.ssl.trustStorePassword= before -Dspring.config.location= & -jar args i was able to successfully invoke my rest call over https.

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In case your host sits behind firewall/proxy , use following command in cmd:

keytool -J-Dhttps.proxyHost=<proxy_hostname> -J-Dhttps.proxyPort=<proxy_port> -printcert -rfc -sslserver <remote_host_name:remote_ssl_port>

Replace <proxy_hostname> and <proxy_port> with the HTTP proxy server that is configured. Replace <remote_host_name:remote_ssl_port> with one of the remote host (basically url) and port having the certification problem.

Take the last certificate content printed and copy it (also copy begin and end certificate). Paste it in text file and give .crt extension to it . Now import this certificate to cacerts using java keytool command and it should work .

keytool -importcert -file <filename>.crt -alias randomaliasname -keystore %JAVA_HOME%/jre/lib/security/cacerts -storepass changeit

---

I ran into same issue but updating wrong jre on my linux machine. It is highly likely that tomcat is using different jre and your cli prompt is configured to use a different jre.

Make sure you are picking up the correct jre.

Step #1:

ps -ef | grep tomcat

You will see some thing like:

root     29855     1  3 17:54 pts/3    00:00:42 /usr/java/jdk1.7.0_79/jre/bin/java 

Now use this:

keytool -import -alias example -keystore  /usr/java/jdk1.7.0_79/jre/lib/security/cacerts -file cert.cer
PWD: changeit

*.cer file can be geneated as shown below: (or you can use your own)

openssl x509 -in cert.pem -outform pem -outform der -out cert.cer

---

If you are still getting this error

Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid 
certification path to requested target

after executing the below command

keytool -import -alias certificatealias -keystore C:\Program Files\Java\jre1.8.0_151\lib\security\cacerts -file certificate.cer

Then there is some issue in JDK. Try to install JDK from a trusted provider. Once you reinstalled it from trusted provider you won't face this issue.

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1-First of all, import you'r crt file into {JAVA_HOME}/jre/security/cacerts, if you still faced with this exception, change you'r jdk version. For example from jdk1.8.0_17 to jdk1.8.0_231

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Here normally this kind of exception occurs when there is mismatch in the PATH of trusted certificate. Check the configuration or path where this server certificate is required for secured communication.

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It's addition to the answer https://stackoverflow.com/a/36427118/1491414. Thanks @MagGGG

Please make sure you have administrator permission

Please use double quotes for the keystore path (-keystore C:\Program Files (x86)\Java\jre1.6.0_22\lib\security\cacerts") because in Windows OS the default installs location will be Program Files and you will get an error because of space between Program Files.

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I fixed this using below method-

Copy url which is having connecting issue Go to Android Studio->Settings->Http settings In 'Test Connection', paste that url and press ok On Ok click, Android Studio will ask to import certificate of that url, import it That's it. Nothing else to be done and my issue was gone. No need to restart studio as well.

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