iPhone Dev team has released PwnageTool 4.2 for iOS 4.2.1 untethered jailbreak. The tool will allow user to jailbreak iOS 4.2.1 on all devices including iPhone 4 on Verizon Wireless network. Those who rely on ultrasn0w unlock, can use pwnagetool  to restore to a custom 4.2.1 pre-jailbroken IPSW and retain their current baseband and unlock their phones. 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: iPhone3G iPhone3GS iPhone4 iPhone4-Verizon iPod touch 3G iPod touch 4G iPad AppleTV 2G PwnageTool also includes two very recent improvements to the 4.2.1 JB:  iBooks was just fixed by @comex and @pushfix last night so that it works as intended on DRMed books, and the wifi problem on AppleTV 2G was fixed by @nitotv, @DHowett, and @saurik.  Both of these fixes will also be available in upcoming Cydia package updates, so if you’re already jailbroken you can wait for those updates rather than restore and jailbreak again. 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’s limerain 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 Instructions for jailbreaking using PwnageTool are similar to the last release, simply follow them as posted here. Select iOS 4.2.1 IPSW file where required. For instructions on how to unlock the iPhone with Ultrasn0w you can follow the guide posted here. Download PwnageTool 4.2 for Mac Download iOS 4.2.1 for iPhone, iPad, iPod touch and Apple TV 2G Download and install the latest version of iTunes. If you do end up trying the PwnageTool 4.2 jailbreak, please let us know how it goes in the comments section below. And, as usual, stay tuned by following us on Twitter and/or subscribing to our RSS feed to keep up to date regarding the current state of jailbreaks with tutorials for the iPhone, iPod Touch, and iPod. Authors:

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