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Comment by pilif | Hacker News Reader

The encryption hasn't quite been cracked. This tool is just brute-forcing the passcode, which by default is 4 digits long, so it wouldn't take that long to brute-force that anyways.

Also, the tool seems to perform an online attack with the phone connected, which means that Apple will be able to stop this from going on.

Seing that only an online attack can be done hints at the fact that the key derivation method that turns the 4 digit passcode into the AES key isn't known (yet).

I'd say that you are (still) pretty save if you use the longer password instead of the passcode and as long as the tool requires the phone to be connected, we can count on Apple patching the issue.

It's funny how these articles always talk about having "cracked the AES encryption" when all they do is brute-forcing a password.

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Limiting your keyspace to 10000 combinations is insecure, there's nothing more you need to say really.

The difference between the simple passcode and the complex password is the difference between a little padlock and a vault door. It shouldn't be news, except that the fundamentals of encryption aren't well-known by the public.

It doesn't limit it to that, it defaults to that.

You can use a longer alphanumeric pass code if you'd rather, it's an option in settings.

As with all security convenience is played off against security. For most people (who in reality aren't likely to be targeted by such an attack and aren't storing much in the way of critical data on their phones) a four digit pass doesn't seem completely unreasonable.

On top of that, a lot of companies have the requirement that once you hook up your corporate exchange to your iPhone, you have to have a >4 digit password (as in the iPhone forces you to change to a longer password)

Exchange can also enforce a shorter time limit before the phone auto-locks. One of the reasons I was glad to dump the Exchange account from my phone when a client project ended.

It's not just the passcode they are recovering. That recovery requires the phone, but there's also the key reocvery and bit-to-bit image copy. The ElcomSoft describes the 3 statges:

- Extract hardware-dependent keys, file system keys and escrow keys from the device; - Recover the passcode (subject to passcode length and complexity); - Obtain bit-to-bit copy of device storage.

Isn't there this setting that says "wipe my iPhone after ten failed attempts"? I imagine that would be quite an effective solution.

Is there a way to copy the data on an iphone bit for bit before trying to guess the passcode?

If it gets wiped, just reimage and start where you left off.

When an iPhone 3GS or newer iOS device wipes itself, it clears the key out of a protected memory area that's not accessible to iTunes, so that re-loading the bit-for-bit copy won't work.

But couldn't you copy that memory as well? Eventually the 1's and 0's are crossing a bus somewhere and you don't need iTunes for that.

This is why I'm happy that Android has some interesting password entry mechanisms that only exist for the iPhone in the jailbreak arena.

Apple really needs to embrace a non-PIN style password and make a way to login that's not a pain in the ass. A friend has an iPhone with a 9-character pass.. it's secure but impossible to use since it takes about 10 seconds to unlock each time... if the user can't be bothered to put a master password because it's not usable to do so, then it almost doesn't matter if there's hardware encryption anyway.

Compared with Google, Apple's views on security are weak. It's like comparing Google's "customer support" to Apple's... demonstrably weaker.

How many swipes are required to unlock your Android phone? Is there an upper limit? Also, how many hot spots are there on the screen (I assume it's not a free-hand gesture...)?

The swipie unlock that every Android phone I've seen in practice could be represented as a four digit number (actually less, since there's no zero and no repeats IIRC). The only difference I can see between a swipe and a digit is you hold your thumb down and it looks more futuristic.

But Android is still converting those gestures to something that's basically a key which can be exposed to a brute force attack.

Android uses a nine cell unlock pattern which gives you roughly 16 bits. A four digit numeric key gives you between 13 and 14.

So while it's better it's not moving it into the realms where a brute force attack of this nature is off the table, it just goes from about 40 minutes to about 4 hours.

Given that in most instances where this sort of attack is being used the attacker will have stolen the phone and therefore there's no practical time limit, that's not a useful improvement.

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