I’m seeing reports of malvertizements automatically opening PDFs. These PDFs use exploits to try and infect a user’s computer.
It’s very important to make sure that if you have Adobe Reader (or other PDF apps) installed on your computer that you make sure that they are properly patched. I ordinarily commend Secunia PSI as an easy way to help stay on top of patches that may be required for software that is installed on your computer, but it requires admin rights (not good if you’re a standard user) and doesn’t work if you access the internet via a proxy. I certainly couldn’t get it to run on my Win7 box running as a standard user – it came up with a proxy error even though I wasn’t actually using a proxy.
Anyway, it’s available here – who knows, maybe you’ll have more luck.