Apple has been battling against the jailbreak scene for nearly 4 years. Every time hackers find an exploit, Apple is right there to release a software update to patch it. But boot-level exploits, like GeoHot’s Limera1n, are much harder to fix.

In fact, Limera1n continues to be used for iOS 5 jailbreaks on pre-A5 devices. So, Apple had to think outside the box with their latest mobile software update. They had to come up with something to try and slow down the hackers. And they did…

According to the Dev Team, users who upgrade to future versions of iOS 5 won’t be able to downgrade like they previously did. Apple has changed the way that they authenticate software restores, so saved SHSH blobs won’t help.

We touched on this back in June, when the Dev Team first spotted the change. But with everyone updating to iOS 5, it’s definitely worth mentioning again. As of right now, there is no way to downgrade versions of iOS 5 after Apple is done signing.

“Starting with iOS 5 beta, the role of the “APTicket” is changing — it’s being used much like the “BBTicket” has always been used. The LLB and iBoot states of the boot sequence are being refined to depend on the authenticity of the APTicket, which is uniquely generated at each and every restore (in other words, it doesn’t depend merely on your ECID and firmware version…it changes every time you restore, based partly on a random number). This APTicket authentication will happen at every boot, not just at restore time. Because only Apple has the crypto keys to properly sign the per-restore APTicket, replayed APTickets are useless.”

So what does this mean for jailbreakers? Nothing, at the moment. As we reported yesterday, iOS 5 is eligible for a tethered jailbreak, and this doesn’t change that. But this can cause major problems once Apple starts pushing out iOS 5 updates.

As things sit right now, if Apple patches a required exploit with a future version of iOS 5, those who accidentally update would essentially be stuck there. For example, you wouldn’t be able to downgrade from iOS 5.1 firmware to iOS 5.0.

But it’s not over until it’s over. Dev Team frontman MuscleNerd believes there will be workarounds for this issue. And users with saved SHSH blobs should always be able to downgrade to iOS 4 (excluding iPhone 4S users, obviously).

Even though Apple just released iOS 5 yesterday, it’s likely that they won’t push out an update for the next couple of weeks. Let this be a jailbreaker’s reminder to be extremely cautious about updating software in iOS 5. Apple has definitely stepped up its game.

  • night

    Does this mean that if I do not update to ios 5 now, and apple release an update tomorrow (lest say ios 5.01) I will not be able to update to ios 5 anymore? (even if I’m upgradeing from ios 4.x.x)?

    • DomPerignon


    • William

      Of coz not, you can always, always upgrade to the lastest iOS version. It’s the downgrade part that will soon require a workaround, after Apple changes their way of authenticating firmware restore.

  • Hepek

    whats the best way just to upgrade the software without jailbreaking
    Im having problems using snowbrease I get errors 3194 I edit hosts and I get 1600 and after I use tiny umbrela I get 11

    so I only want to get IOS 5 and I dont care about jailbreaking

    iPhone 4

    • Jimmy

      If you don’t care about jailbreaking and you don’t rely on an unlock the best way is to just use either update or restore in iTunes, make sure you edit your hosts file though so it does as it normally would and that is check Apple’s servers, not cydia’s.

      • Hepek

        Jimmy I have a Gevey card and I read it supports iOS5 and like I said I dont want to JB I just want to new software but dont want to upgrade my BB and lose my unlock.

      • Jimmy

        Wouldn’t have a clue either way mate about Gevey so I can’t help you on that front.

    • mmm

      I guess you can do this with Redsn0w, although right now there’s only a Mac version-

    • Spizikes

      If you want to keep your baseband and want to upgrade to i0s 5 without jailbreaking use sn0wbreeze to make a custom firmware. Make sure you have the latest iTunes. Put your iPhone into DFU mode. Shift+restore your sn0wbreeze custom firmware. If it gives you a 1394 error, use iReb. It works.

    • javierE186

      I have Gevey and ultra must be jailbroken, and the normal one you don’t need a jailbreak however it wont work on iOS 5 because iOS 5 updates your Baseband. Only way you can leave your BB 4.10.1 is my preserving your BB. Which means you need something like sn0wbreeze. Either way you will keep on getting those errors sadly (since you get them now after trying it). Guess you have to wait until the programs get a fix.

  • DomPerignon

    After playing around with iOS 5 for a I jailbroke my iPhone 4 and because 65% of my apps didn’t work I downgraded to 4.3.3 with no problem at all

    • QuarterSwede

      Correct. You can always downgrade to iOS 4. This is talking about downgrading from a later version of iOS 5.x to iOS 5.0.

      • Dylan

        Well apple is still signing 4.3.5

  • Sillybear

    Still rocking 4.2.1
    No reason to drop my JB yet!

    • Eddie

      Same. 4.2.1 jabroken with greenpoision. Nothing in 4.3 tempted me enough to bother upgrading and reinstalling all my tweaks. Plus there are always compatibility issues with new firmware.

      I want iOS 5 but am going to be patient and wait for a good jailbreak.

      • fitu

        thought I was the only one with 4.2.1 jailbroken device lol

      • Steve

        I’m still on 4.1 for my 3GS. lol So whenever i do get this iphone 4S it will be a major update, with hopefully an untethered jailbreak by then. fingers crossed 🙂

      • XepptizZ

        Good old 4.2.1 :), waiting for the untether til then

    • DebTym

      mine right now is still 4.2.1 Very stable.^^

  • Cyril

    Actually there is a way to downgrade from iOS 5 to 4.3.3 again:) Found it on this site It works but it’s pretty long…

  • Taylor Harris

    First sentence, second paragraph: Don’t you mean iOS “4” jailbreaks on pre-A5 devices instead of iOS “5”?

    • MisterExx

      No, limera1n can be used to jailbreak iOS 5 on iPhone 4 and older devices. There’s no jailbreak for the 4S yet.

      • Elite

        Is this jailbreak tethered or untethered?

      • fdxgncgfn

        he means the exploit, not the jailbreak.

  • pipo

    if you want to restore from 4.3.5 you go to itunes,put your phone in DFU mode and select restore that means that you have already downloaded ios 5.While restoring if you get the error 3194 you have to download tinyumbrella and do what it does in this video it might say that it is for 4.3.3 firmware but it will sure work

  • Mark

    I continue to get an error “cannot connect to server at this time” response when I choose the ipsw from my desktop that is jailbroken and the same response on auto update. Any ideas?

    • Burge

      If you have tinyumbrella you need to uncheck …sets host to Cydia box…it’s under the advanced tab

  • Daniel

    There isn’t any reason to update 5.0 to 5.1… the iOS just came out, i doubt that serious bug will be fixed or somthin’ like that. So as long as I have my iOS 4 SHSH blobs saved, and my custom IPSW and im on 5.0 Im safe 😛

  • Cooper

    If there’s no Jailbreaking where’s Apple going to get their iOS ideas?

    • Alex

      Apple can’t afford losing jailbreaking it’s vital to promoting their devices.

      If it does block jailbreaking… I would invite all jailbreakers to push for improving android OS and to make it more user friendly. Right now android is good but it needs simplification, and it needs to remove some of it’s junk… Once it’s cleaned up and user friendly it can compete with apple.

      As of now iPhone is the best!!!

      Most importantly android needs a improved browser

      • Goofygreek

        Theres a rom you can use to change almost any androids layout. It’s called cyanogenmod and its great. Fully customizable. You can even make work identically to iOS.

    • MisterExx

      Hahaha!! WINNER!!

      • Alex

        Duh WINNING

    • John Moraitis


  • Alex

    If I upgrade to iOS 5 can I downgrade to 4.3.3

    Obviously I still have shsh blob saved.

    I plan on using the new Redsn0w to build a custom firmware to go up to iOS 5 but not jailbreak.

    Reason being is I use a gevey so I need my baseband preserved. I heard the iOS 5 contains a baseband that is not compatible with the GEVEY sim unlock.

    Update ultrasn0w and help us with a unlock for higher baseband iPhone 4… Or even Apple by “pushing” for a unlock you get people to buy iPhones. Think 1 million people use Apple iPhones on TMOBILE.

    This is a lot of units.

    BTW did I hear right? Sprint/Verizon are
    WORLD phones!!!!!

    Unlocked gsm & CDMA technology!!

    I’m looking to buy the SPRINT iPhone 4S

  • iMarc

    Don’t hold your breath for any newer baseband additions to ultrasn0w as the dev teams seem to have hit a brick wall.

  • Matt

    Ok I am on 5.0 and so let’s say Apple releases a new firmware. Over into a bond where I have to restore my phone but only want to stay on 5.0 will I be able to restore to 5.0 even apple isn’t signing that firmware?

  • Stupid apple against what we do

  • i updated to ios 5, but i heard that ultrasnow 1.2.3 is still not updated,, so i downgraded to 4.3.3 but after all stuff, (tried with both Pwn & Snow & Redsnow) when i completely install ultrasnow 1.2.3 and also rebooted sucessfully; I’m still not getting network signals, Y… its just says “Searching” nothing more, I’m on 3gs, 6.15.00,, plz help, plzzzz, i got to away from itunes for a week, plz help guys!

    • When you upgrade iOS, it upgrades the baseband as well. But you can’t downgrade the baseband, so you’re stuck with the iOS 5 baseband.


  • Rotflmfao

    lol im still on 4.0 i downgraded from 4.2.1 but i miss the custom boot logos

  • Apple are just f*ckers!!!!!

    • Joege

      Apple, give you the iDevice…… So, they are not fuckers

      • Omnicron13

        Apple doesn’t give anything to you. You buy the device. Even if your try to say AT&T gives it to discounted. You make a $199-$399 down payment and make monthly installments per month for 10 months

      • Omnicron13

        Apple doesn’t give anything to you. You buy the device.

  • Nicholas

    Can’t wait 4 unthethered jailbreak 4 ios5….have never and will never pay 4 anything on the appstore….thank god 4 installous..lolz

  • ak47

    shit, this makes me think a thousand times before i upgrade to ios 5

  • kokhean

    I’m still on 4.3.3 (iPhone 3GS, Factory Unlocked). I’ll get the iPhone 4S on iOS 5 and use my jailbroken 3GS as an iPod touch.

  • DK

    This is not a nice news

  • vivek

    when is the untethered jailbreak of ios5 going to release.?

  • 1337inside

    Great i readed all of this after i did update to iOS5 and after jailbreak that is untethered, now i got nothing on iphone lol…. guess i’ll wait for tethered jailbreak, updating OS later after i install iphone with tethered jailbreak doesn’t concern me as i never do update after

  • bri


  • well too bad jailbreak is already available for it and t works just fine