A5 Can Now Be Downgraded to 5.x.x

[zig9449]

ih8sn0w's method isn't public yet, but theoretically, it could be used to downgrade the 4S and iPad 2 to 5.0 and 5.0.1 from 5.1 (assuming SHSH blobs for the iOS version in question are saved either locally or by Cydia). Technically it can also be used to downgrade A4 devices, but this is unnecessary because Geohot's limera1n exploit already provides this functionality and unlike ih8sn0w's loophole, cannot be patched.

Yeah....thats what this thread is about. And yes....we know it isn't public yet....if it was....everyone would know.

[Ads]

[dan448899]

Yeah....thats what this thread is about. And yes....we know it isn't public yet....if it was....everyone would know.

Just clarifying for pianoman.

[pianoman]

Thanks all! Keep us posted. I'd like to try 5.1 but be able to get back to 5.0.1 JB.

[zig9449]

Thanks all! Keep us posted. I'd like to try 5.1 but be able to get back to 5.0.1 JB.

I thought you had SHSH for 5.0.1?

[pianoman]

I thought you had SHSH for 5.0.1?

I do. I have 5.0 blobs and 5.0.1 blobs because Cydia saved them for me while JB. I'm on A5 devices, phone & tablet.

[zig9449]

I do. I have 5.0 blobs and 5.0.1 blobs because Cydia saved them for me while JB. I'm on A5 devices, phone & tablet.

Oh...A5. My bad. Hopefully iH8sn0w releases this soon.

Tho I'm not sure if this is enough for me to get a 4S. I have been waiting for a bootrom exploit to get it. That way I can restore to custom Ipsw's.

[pianoman]

Oh...A5. My bad. Hopefully iH8sn0w releases this soon.

Tho I'm not sure if this is enough for me to get a 4S. I have been waiting for a bootrom exploit to get it. That way I can restore to custom Ipsw's.

Ah -- there's the answer to the $64,000 question. Am I understanding you correctly that it was a boot rom exploit that enabled the perpetual downgrade ability in A4? (boot rom as opposed a software exploit)... Then if yes to that - the great thing about iH8sn0w's find here is that it's ALSO a boot rom exploit that will open up IPSW custom builds using 5.x.x blobs for us A5 people all the way thru iOS 5 updates perpetually??? If so - how exciting...

[zig9449]

Ah -- there's the answer to the $64,000 question. Am I understanding you correctly that it was a boot rom exploit that enabled the perpetual downgrade ability in A4? (boot rom as opposed a software exploit)... Then if yes to that - the great thing about iH8sn0w's find here is that it's ALSO a boot rom exploit that will open up IPSW custom builds using 5.x.x blobs for us A5 people all the way thru iOS 5 updates perpetually??? If so - how exciting...

I highly highly doubt there is a bootrom exploit for A5.
iH8sn0w said there is a loop hole in the APTicket system allowing A5 devices to be downgraded.....that's something entirely different from a bottom exploit for A5 devices.

(tho a bootrom exploit is why A4 devices can restore to a custom Ipsw)

There is still no bottom exploit. If there was...there would be a tethered jailbreak for A5 devices.

The iPhone 4 (A4 devices) will always have a jailbreak no matter what new iOS comes out...this is why tethered jailbreaks are released so quickly.

This is because the A4 chip has a bootrom exploit that can always be used to jailbroken. Sometimes it takes a little time to get an untethered...but the tethered jailbreaks are released almost immediately after a new iOS is released...for this reason.

[Jmills87]

zig is right, no bootrom exploit at all, the method uses a loophole in the APTicket system. It is still an exploit, but you can hardly even call it that.

[pianoman]

zig is right, no bootrom exploit at all, the method uses a loophole in the APTicket system. It is still an exploit, but you can hardly even call it that.

Ah ok. Makes sense. But the effect is the same in that for A5 devices here out - we'll always be able to downgrade. Right?