Looks like there is a fix now for the malicious TIFF exploit in Safari in iPhone 1.1.1. The only catch, you have to have a hacked iPhone! Seems the hackers are more on top for fixing things for the iPhone than Apple! (Apple, as I understand it, is still trying to get iTunes to charge you 99 cents to fix the exploit.)
http://www.tuaw.com/2007/10/29/confirmed-jailbreak-appsnapp-fixes-tiff-exploit-hole-in-iphone/
http://www.tuaw.com/2007/10/29/confirmed-jailbreak-appsnapp-fixes-tiff-exploit-hole-in-iphone/