[hacking18]

Basic security measures goes a long way. The latest version of 1.6 does not have known vulnerabilities and most hackers are focusing on the 1.8 series now.

you just said it known, there are much exploits that are not known in public, there are a lot of zero day exploits which the public doesnt know about because they are detected only when a major site or server got hacked with it and yes hackers focus on the latest versions because they already have a lot from the previous versions