updated 12:10 pm EST, Fri February 8, 2008
New iPhone 1.1.2 unlock
An iPhone hacker has discovered a new way to unlock Apple's iPhone firmware version 1.1.2 without the need to downgrade to a prior firmware revision and then re-upgrade after unlocking the device. The unlock technique relies on a bug that allows hackers to erase the contents of memory within a range of specific addresses, coupled with a second bug that allows users to copy data before validation occurs.
"The first exploit I found, at around 4 AM last night, was the -0x20000 exploit," wrote George Hotz, the discoverer of the new unlock method. "I finally found a working exploit about 23 hours into my search for the software unlock. The explict addresses 0xA03D0000-0xA03F0000 will always erase."
Another user has posted a tutorial describing the process of jailbreaking and unlocking an iPhone, making use of the newly discovered exploit.