To make sure you don’t get hacked you should always install updates and avoid any unknown websites or apps. If you don’t use the internet services on the TV, don’t have it connected, with no connection an attacker has no way of getting on to it.
Like smartphones, Smart TVs can be hacked, there are vulnerabilities that can let other people have access the files and use the camera! To make it worse, because the TV only has a single profile, if someone manages to hack it they can see everything and anything on it. Not like a computer where there are multiple profiles meaning the hacker would have to hack into each one separately.
With over 67 million “smart” TV’s sold in 2012 the vulnerability issue has become an increasingly dangerous one. Since this issue was raised Samsung has looked in to the vulnerabilities and have found numerous bugs which they were able to patch. Hopefully this will make smart TV’s harder to be compromised.