I received this exact error today trying to connect via KVM. The method of editing the file java.security did not work on my computer unfortunately (Ubuntu desktop client).

Solution

1. Go to Java Control Panel:
   javaws -viewer

2. Go to Advanced tab
   -> then find Advanced Security Settings (near end of list)
   -> tick all the TLS settings

3. Go to Security tab
   -> click Edit Site List.. (this is a list of Exception sites)
   -> click Add -> now add the IP of the machine you were connecting to .. it should look like this:
   https://172.1.2.3/

4. Click OK and then Apply the changes.