What’s in a name? Well in the case of an HFS volume name on iOS, an untether exploit — as the Chronic Dev Team revealed last week with an untether for the 4.2.1 jailbreak, which had previously been a tethered JB for most recent devices since 4.2.1’s release in November.
With their permission, we’ve incorporated their 4.2.1 “feedface” untether into today’s PwnageTool 4.2. This means iPhone unlockers can safely restore to a custom 4.2.1 pre-jailbroken IPSW and retain their current baseband and unlock. PwnageTool also supports all the other 4.2.1 devices other than iPod touch 2G:
The various components to the 4.2.1 untether (including a second exploit involving Mach-o headers) were worked out by 0naj, posixninja, and pod2g, and a nice writeup by 0naj is available on the wiki. The actual injection method uses geohot’slimerain exploit for most devices. And even though 4.3 is just around the corner, the exploit used has already been closed in the latest 4.3 betas, so it made sense for the 4.2.1 untether to be released when it was. It also appears that a security researcher named @i0n1c has a 4.3 untether ready for when Apple releases the final 4.3 FW, so it may not be a long wait at all with 4.3!
Official Bittorent Releases
PwnageTool_4.2.dmg -> PwnageTool_4.2.dmg.6176918.TPB.torrent
SHA1 Sum = 1c0d5ea45464e336fcb38c644dc125c3a16b5493
Mirror : PwnageTool_4.2.dmg.6176918.TPB.Mirror