Over the weekend I spent more time looking into the zero-day LNK (shortcut) Windows vulnerability that Aleks blogged about last week. It’s now been classified as CVE-2010-2568 and is being actively exploited in the wild.
My main conclusion is that this vulnerability is a fundamental part of how Windows handles LNK files. This means there are two huge negatives – firstly, as this functionality is pretty standard, it's going to be harder to create effective generic detections which don't cause false positives.
We’ve released generic detection for malicious LNK files which try to exploit the feature. I think that the LNK format will start receiving a lot more attention now, both from the good guys, and the bad, so do take a look at the mitigations put up by Microsoft. I’m sure it will be time well spent, as I fully expect this vulnerability to be widely exploited while we’re waiting for the patch.