iPhone Upgrading to IOS 8.1.2 from 6.x and Jailbreaking

Discussion in 'Jailbreaks and iOS Hacks' started by SeattleDavid, Apr 17, 2015.

  1. SeattleDavid macrumors newbie

    Joined:
    Apr 17, 2015
    #1
    I have a backup of my phone with IOS 6.x on a Windows box. I can restore to it fine but I am unable to upgrade to 8.1.2 as opposed to 8.3 so I can jailbreak the phone again but with the newer IOS. I understand that 8.1.2 is no longer signed which is causing the issue. Is there any way to get 8.1.2 on this phone?

    Thank you!
     
  2. Jumpie macrumors 6502a

    Jumpie

    Joined:
    Jul 7, 2008
    Location:
    Atlanta
  3. SeattleDavid thread starter macrumors newbie

    Joined:
    Apr 17, 2015
    #3
    Why not utilize a hostname rewrite of the Apple authentication server gs.apple.com to another IP which allows the authorization of older versions? Has anyone done this?
     
  4. C DM macrumors Westmere

    Joined:
    Oct 17, 2011
    #4
    What other server would authorize older (or any) versions?
     
  5. SeattleDavid thread starter macrumors newbie

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    Apr 17, 2015
    #5
  6. C DM macrumors Westmere

    Joined:
    Oct 17, 2011
    #6
    That's why after all these years this is still something doesn't exit, right? There's pretty much quite a bit less exploitable out there for anything beyond iPhone 4 at best, especially on that level.
     
  7. SeattleDavid thread starter macrumors newbie

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    Apr 17, 2015
  8. eyoungren macrumors P6

    eyoungren

    Joined:
    Aug 31, 2011
    Location:
    Phoenix • 85037
    #8
    It works probably like you think it works.

    But here is the problem.

    Apple stopped using SHSH blobs for authentication with iOS 7.

    The creator just very recently started some work that might possibly allow downgrades again but as of right now - no workie.
     
  9. zorinlynx macrumors 601

    zorinlynx

    Joined:
    May 31, 2007
    Location:
    Florida, USA
    #9
    The problem is the bootrom.

    The bootrom has code in it that verifies the cryptographic signature of the OS you try to load on the device. If it's not signed, it won't install.

    You don't have the private key required to sign releases, so you're SOL. The key is unique for each device since the UUID is included in the signature.

    Unless you could obtain Apple's master key, installing old versions of iOS is impossible. it would be convenient if that key would be leaked, but I think Apple employees value their job too much. ;)
     
  10. SeattleDavid thread starter macrumors newbie

    Joined:
    Apr 17, 2015
    #10
    That makes more sense. Thank you eyoungren and zorinlynx.
     

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