I use the internet.
I have an older computer (a tad on the slow side) so I don’t download much other than the occasional Windows 98 update.
Given this behavior, can I still get a computer virus (from the internet) simply by visiting a site? Or do I have to actually download and/or execute a program?
How about e-mail? Can I get infected by just receiving a tainted e-mail? Or do I have to open an attachment.
There are always exceptions, but generally you don’t get a virus simply by visiting a site. (Nimda, which did try to download it to your computer if you visited an infected site, only infected if you clicked on the warning screen and agreed to install the virus.) You usually have to download/execute a program.
Sites can sneak spyware on your computer using ActiveX controls, but viruses aren’t spread this way.
E-mail is like always. You need to click on an infected attachment to get infected. Microsoft Outlook and Outlook Express once had a security hole that did allow infected merely by getting the e-mail under certain conditions, but that’s been patched for nearly two years, and no significant viruses took advantage of it.
There are a number of vulnerabilities in unpatched copies of Internet Explorer and Outlook Express which can theoretically be exploited just by viewing a malicious webpage or email, even if you don’t execute anything or open attachments. It is very important to apply all Critical Updates from Windows Update to fix these security holes.
A new cumulative patch was released two days ago.
OE can be made a lot safer by setting it to open emails in the Restricted sites zone under Tools|Options|Security. This is the default setting for OE6, but wasn’t for 5 and earlier.
Note that the first response more or less addresses “correct software behavior” while the second addresses “hey, we goofed” typical software behavior. Hence the differences between them.
You’re not supposed to get a virus/worm just be looking at a web page or by displaying the subject line of an email, but hey, they goofed. Will continue to goof. Etc.
Avoiding the most common Internet software programs greatly reduces the chances of such problems.
Basically no non-trivial program will be safe. But if you use programs unlikely to be targetted, that helps.
Like Number said, but (to add to the general sense of paranoia)
It makes Number’s comment on updates even more appropriate.
As you are using W98, you are safe from this particular nasty.