Java: InvalidAlgorithmParameterException Prime size must be multiple of 64

Question

I implemented a Java program that will connect and execute a command in a remote server using JSCH. The problem is that whenever I tried to connect to the server, I got the

Answer 1

Add this line of code after you have the Session instance:

public static Session createSession(Server srv){
   JSch js = new JSch();
   try {
      Session s = js.getSession(srv.getUser().getUsername(), srv.getAddress(), 22);
      s.setPassword(srv.getUser().getPassword());
      Properties config = new Properties();
      config.put("StrictHostKeyChecking", "no");
      config.put("PreferredAuthentications", "password");
      config.put("kex", "diffie-hellman-group1-sha1");
      s.setConfig(config);
      ...

The line to be added is: config.put("kex", "diffie-hellman-group1-sha1");