Are you using Internet Explorer? Read this.
http://www.bbc.co.uk/news/technology-12067295
Get the latest fix,alternatively install Firefox.
eddie
Agreed, a much better browser.

You mean that browser thats well reknown for having more bugs that the CIA? Its certainly not a browser I would recommend on a security basis 
For IE users, there is a perfectly good workaround for this. Nice to see the BBC have made a half-arsed job of reporting anything properly, but then I guess even they would argue they have to dumb it down for their most dense of stupid audience....
You worry me when you say things like that TB!!
I have it installed...............but I also have F-Secure!!
Don't please tell me that is also full of bugs

Problem with software flaws is that targetted attacks will bypass AV etc (until it tries to write to disk, when the AV driver
will may pick it up).
Add to the fact, that due to penile complexes, most people are retarded enough to run as an Administrator user, thus the compromised software runs with Admin rights, thus the injected malware runs as Admin, thus has free reign over your system.
If people bother to follow well published, sensible precautions, thay'd be much safer online. In the same way you wouldn't stick your alarm PIN on a postit above the alarm panel, and leave the front door open when you go out.