exception - PKIX path building failed in Java application

Question

I have been struggling for almost one week to get my applications up running after moving my applications from Windows 2000 to Windows 2008 R2 Server.

The procedure:

1. Installed Java JDK 1.7.0_25
2. Set system environment variable JAVA_HOME to C:Progra~1Javajdk1.7.0_25
3. Imported the certificate into cacerts with keytool
4. Ensured that the certificate exists in keytool with -list.

I have tried to repeat step 3 with InstallCert to ensure that i havent messed anything up.

The above methods did not solve my problem, so i tried to do it programmatically:

System.setProperty("javax.net.ssl.trustStore",
"C:/Progra~1/Java/jdk1.7.0_25/jre/lib/security/cacerts");
System.setProperty("javax.net.ssl.trustStorePassword", "changeit");

Still without any luck. I am stuck and not quite sure which direction to go from here.

Stack trace:

javax.net.ssl.SSLHandshakeException: 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.ssl.Alerts.getSSLException(Alerts.java:192)
    at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1886)
    at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:276)
    at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:270)
    at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1341)
    at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:153)
    at sun.security.ssl.Handshaker.processLoop(Handshaker.java:868)
    at sun.security.ssl.Handshaker.process_record(Handshaker.java:804)
    at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1016)
    at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1312)
    at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1339)
    at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1323)
    at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:515)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:153)
    at util.SMS.send(SMS.java:93)
    at domain.ActivationSMSSenderMain.sendActivationMessagesToCustomers(ActivationSMSSenderMain.java:80)
    at domain.ActivationSMSSenderMain.<init>(ActivationSMSSenderMain.java:44)
    at domain.ActivationSMSSenderMain.main(ActivationSMSSenderMain.java:341)
Caused by: 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:385)
    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:326)
    at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:231)
    at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:126)
    at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1323)
    ... 14 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:196)
    at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:268)
    at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:380)
    ... 20 more

UPDATE:

Both System.out.println(System.getProperty("javax.net.ssl.trustStore")); and System.out.println(System.getProperty("javax.net.ssl.keyStore"));

returns null.

Answer 1

I ran into similar issues whose cause and solution turned out both to be rather simple:

Main Cause: Did not import the proper cert using keytool

NOTE: Only import root CA (or your own self-signed) certificates

NOTE: don't import an intermediate, non certificate chain root cert

Solution Example for imap.gmail.com

1. Determine the root CA cert:

   openssl s_client -showcerts -connect imap.gmail.com:993
   

   in this case we find the root CA is Equifax Secure Certificate Authority

2. Download root CA cert.
3. Verify downloaded cert has proper SHA-1 and/or MD5 fingerprints by comparing with info found here

4. Import cert for javax.net.ssl.trustStore:

   keytool -import -alias gmail_imap -file Equifax_Secure_Certificate_Authority.pem
   

5. Run your java code