How do hackers hack into one's computer?

How do hackers exactly intrude our computer?
Do they first scan for open ports?
Could someone please explain this and how I can be protected by these attacks?

 

If you are behind a NAT router, the only way is to plant something inside your PC by taking the user into confidence and making them run a program.

 

hello.........does port forwarding in nat router for games and torrent clients make one vulnerable to such attacks..?

 

Port forwarding to accomodate an app that needs to receive incoming traffic makes that application part of your attackable surface. If that particular application has any vulnerabilities that are exploitable from the net, you could potentially be vulnerable to those specific attacks.

 

what could then be the measures one can....one should take to protect one's system in the eventuality of the indespensbilty of using the apps requiring port forwarding....? In my case i have....xp pro sp3....kis2009,MBAM real time, returnil paid and sandboxie paid

 

Any application that's exposed to incoming internet traffic or that opens new/unknown content should be as isolated as possible from the operating system. I use a completely different security setup and am not that familiar with Sandboxie. If the apps/games will run inside of Sandboxie, run them there. This would also apply to any applications or media files you download with the torrent software. I'd be more concerned about the downloaded material than the torrent software itself.

Quite often the port number an application listens on will tell you what application has opened it. If I scanned a PC and found port 10114 was open, I'd expect to find µTorrent running. If it was port 43287, I'd expect to see Shareaza behind it. This type of association holds true for a lot of applications and services. It's a good practice to change the default port an application listens on whenever possible. Just make sure that the port you select won't be used by something else on your system at the same time.

 

Port and Expl0it scanners is the easy way 2 see if the pc is vulnerable?

nbtstat -a *TARGET*

Check out your NETBIOS status ! (Secure It if not secured)

 

Do you mean: "DisableNetBIOS over TCP/IP" ?

What will someone gain if he disables(secures) NETBIOS?
And what if Netbios is not secured?