- Vulnerability, Exploit: geohot
This geohot's implementation of the usb_control_msg(0x21, 2) Exploit. It has been released for Windows and undoubtedly a Mac version is to follow. It will jailbreak all devices on 3.1, 3.1.1, and 3.1.2. It will even jailbreak OTB iPhone 3GS and iPod touch (3rd generation).
How to use
All you have to do is head to http://www.blackra1n.com and download the application on to your computer. Then, plug in your iPhone (2G, 3G or 3GS)/iPod Touch (1st, 2nd or 3rd Gen) and press "Make it ra1n". Then you wait. If the phone is stuck in DFU, just press "make it ra1n" again
GeoHot's blog: http://iphonejtag.blogspot.com
iPhone Dev-Team's offerings (PwnageTool and, when released, Redsn0w): http://blog.iphone-dev.org