For developers who are testing iOS 6 beta which was released by Apple at WWDC 2012 session, dev team have pushed tethered jailbreak of iOS 6 beta, Redsn0w 0.9.13 dev1 for Windows and Mac.
UNLOCKERS AND THOSE PRESERVING THEIR UNLOCKABLE BASEBANDS SHOULD STAY FAR AWAY FROM THIS! You will very likely lose your unlockable baseband if you try to install iOS 6.
THIS JAILBREAK IS INTENDED ONLY FOR DEVELOPERS OF JAILBROKEN APPS! There are just too many broken components (Apple’s official apps, 3rd-party App Store apps, Cydia apps, etc) for this to be useful to anyone but those truly looking to fix bugs in their iOS 6 jailbroken apps.
CYDIA WILL NOT BE INSTALLED because it just hasn’t had time to be updated to the new SDK. The only access you’ll get to the device is through SSH or afc2. If you don’t know what either of those are, you shouldn’t be using this developer version of redsn0w!
THIS REDSN0W WILL NOT HACTIVATE! You need to be an iOS developer with a registered UDID to get past the activation screens. PLEASE DON’T PIRATE APPLE SOFTWARE! Only registered devs with Macs can develop iOS applications,and only those people will have legitimate access to the beta IPSWs.
THIS IS A TETHERED JAILBREAK ONLY! No new exploits are being exposed with this jailbreak (it uses geohot’s limera1n bootrom exploit), but that comes at a cost. You will need to use redsn0w’s “Just boot” button to be able to use many things, including Safari. If you see Safari or iBooks crash when you open them, it’s because you didn’t boot tethered.
You must point redsn0w at your IPSW the first time you “Jailbreak” and “Just boot” tethered because that IPSW is only available to developers, and redsn0w can’t automatically fetch the pieces it needs from it. By the time you’ve done a “Just boot” tethered JB though, redsn0w has cached all the files it needs from the IPSW so you won’t need to point redsn0w at it any longer.