Safari's 'open "safe" files' option unsafe

Securitytracker reports on a new security flaw found in OSX.
There is a flaw in the checking of disk images, so that a maliciously crafted .dmg file can cause a kernal panic on your Mac, possibly allowing for arbitrary code execution. The problem is that Safari is set to automatically open "safe" files after downloading them, and that means that clicking on a link that triggers the download of a malicious .dmg file will crash your machine.
The best solution is to deactivite Safari's "Open 'safe' files after downloading" option (taht's in Safari's Preferences, under General). And also, be careful before opening files that come from a dubious source.