If you use µTorrent, please make sure to upgrade to the latest version, 1.7.6. All previous versions have a bug where a remote user could crash your copy of µTorrent and in some cases, possibly even get into your PC.

So again, if you use µTorrent, please make sure you’re running the latest version!

UPDATE: I almost forgot — this exploit applies to the BitTorrent branded client too as it’s just µTorrent with a different name.

UPDATE #2: If you’d like to read more on this, TorrentFreak has a good article.

UPDATE #3 (1/21): µTorrent v1.6.1 is immune and safe to use. All other versions besides 1.7.6 and the latest 1.8.x alpha are unsafe (that includes 1.6.0).