Passcodes Prove Predictable

mikejuk writes "Research reveals something we all suspected but couldn't prove — in a four digit pin the most popular first digit is one, the most popular second digit is two. Entropy only really kicks in on the third and fourth digits. What is more looking at the frequencies of four digit groups just 10 different passcodes would be enough to unlock one in seven iPhones!"

Comments

Easy to fix!

[Daetrin]

This is simple to fix! Everyone, make sure to start all your passcodes with "4" instead of "1" and this attack will be easily foiled!

Repost

[swb]

Isn't this a repost of the iPhone app developer who made the photo-graphing lock screen and kept anonymous stats of the "passcodes" people entered into his lock-screen-like lock screen?

Re:Physical security

[cbiltcliffe]

Here's a clue: don't let anyone mess with your phone when you're not there to stop them.

Really? Do you hear what you're saying?

Benford's Law

[Bobtree]

Since people are likely to use passcodes based on real-world numbers so they can be remembered, perhaps Benford's law applies.

http://en.wikipedia.org/wiki/Benford's_law

Re:Benford's Law

[Anonymous Coward]

Since people are likely to use passcodes based on real-world numbers so they can be remembered

Rather than using real numbers, people should try complex passcodes. My iPhone is locked with: 0000+9999i

Re:9991

[Caerdwyn]

But if the best code is 9991, then a thief should try it first, which would make it not the best code, which would make something else the best code, which would make some other code the one thieves would try first, which ...

But I surely cannot choose the wine in front of me.

Re:Entropy of passcode space

[elsurexiste]

I have said this once or twice in the past, but what the hell. :)

I did research on this subject and you, sir, nailed it. People don't choose numbers: they choose patterns, all the time. The most common passwords are, unsurprisingly, lines. A few are one or two repeating digits. People also have a fondness of diagonals and spirals, although this is noticeable when there are 16 or more buttons. That being said, I'm surprised that 5683 is so common.