Trojan horses and firewalls

[Tefler]

Given that Norton Antivirus and Internet Security (including Firewall) are running an a computer, how does it still get infected with Trojan horses? How do the malicious people get round the firewall? Is there anything that can be done to lessen the threat?

[gavinbecky]

It depends how quickly the virus protection company update their definitions.

There are many viruses and trojans around. I bet that if you tried them all on a pc infected with a variety of viruses that they would pick a different one up.

I don't think the whole problem of viruses is being tackled. It seems to be a case of stop the individuals problem rather than the root cause.

With so many virus protection companies out there though, it has all become big business............

[mattie]

Because NIS is useless.

Use dedicated antivirus software, Microsoft antispyware (if running XP) and make sure all the latest windows updates are installed.

[Aquariel]

There's also the chance of picking up spyware and trojans from running downloaded software - it might look harmless, but if you don't read the "agreement" then who knows what you might be installing. This is especially important if you have kids!

As long as you have a good firewall/virus checker then you are reasonably well protected, but even the most paranoid security-conscious net users can still get caught out.

New Windows exploits seem to be regularly discovered, giving spyware writers the chance to create something new before everyone has had a chance to patch their system.

It's amazing how many people I know have bought a new PC and didn't even know what a firewall was, or why they would even need one ... and they end up becoming a relay for spam and other assorted nasties.

[boobesque]

adding on to the point that norton is crap, software firewalls are crap too. if you want real security you need a hardware modem. but these can be expensive. a lot of trojans out there disable the firewall or just allow themselves access before anything else. the main problem here is that you have norton firewall. lots of other people do aswell and this gives them the opportunity to study the firewall and search for those exploits. theres not m,uch you can do but stay wary. dont try and test your antivirus or firewall.