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Most common PIN codes (2012)

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Re: Most common PIN codes (2012)

#91

Post by fsckboy »

GoblinSlayer wrote: post #86
fsckboy wrote: post #71

Earlier quoted context omitted.

> Also nothing says you can't use the same PIN for multiple cards he said he can't choose his PIN: > One of my credit unions gives out (randomized) five digit pins

All cards have randomized pins and can later be changed.

no, some cards you choose the PIN from the start and never get a randomized PIN

some banks some place in the world might make it a policy not to set PINs but to force random, you can't definitively say what you are saying, rather we can only go by what he said.

Re: Most common PIN codes (2012)

#92

Post by aidenn0 »

shmuppet wrote: post #82
devnullbrain wrote: post #61

Earlier quoted context omitted.

I'll remember to prioritise 0000 to 2767 for your PINs, then.

Just so you can see the bias to early numbers in the distribution: for i in $(seq 1000000); do echo $[RANDOM%10000]; done | sort -n | uniq -c | sort -rn | gnuplot -e "set terminal dumb; set xtics 1000; plot '

I think this gnuplot command makes the bias much more obvious (and even better with -persist and "set terminal x11"): gnuplot -e "set terminal dumb; set xtics 100; plot 'Compare to the version that discards values over 3e4:

  for i in $(seq 1000000); do x=$((RANDOM)); while test $x -gt 30000;do x=$((RANDOM)); done; echo $((x%10000));      done |sort|uniq -c |sort -rn |gnuplot -e "set terminal dumb; set xtics 100; plot '
Or the version that uses the 32-bit SRANDOM, which reduces the bias by a factor of 2**17:

  for i in $(seq 1000000); do         echo $((SRANDOM%10000));      done | sort -n | uniq -c | sort -rn |gnuplot -e "set terminal dumb; set xtics 100; plot '

Re: Most common PIN codes (2012)

#93

Post by eqvinox »

fsckboy wrote: post #91
GoblinSlayer wrote: post #86

Earlier quoted context omitted.

All cards have randomized pins and can later be changed.

no, some cards you choose the PIN from the start and never get a randomized PIN some banks some place in the world might make it a policy not to set PINs but to force random, you can't definitively say what you are saying, rather we can only go by what he said.

Nothing in this sentence

> One of my credit unions gives out (randomized) five digit pins (although they say if you use an atm that only accepts four digit pins, the first four is enough).

says that the PIN on that card can't be changed.

Re: Most common PIN codes (2012)

#94

Post by eqvinox »

toast0 wrote: post #90
eqvinox wrote: post #55

Earlier quoted context omitted.

Not sure how this is handled in Switzerland, and I don't have good data on this, but I'd say a lot of people in Europe have at least a debit and a credit card with a PIN each. Also nothing says you can't use the same PIN for multiple cards; they're essentially the same security domain anyway ("a piece of plastic in your wallet") — most people don't have "more" and "less" trustworthy cards…

> Also nothing says you can't use the same PIN for multiple cards; they're essentially the same security domain anyway ("a piece of plastic in your wallet") — most people don't have "more" and "less" trustworthy cards… Why not have the same password for all your banking accounts then? But everyone says not to reuse passwords. If someone takes your wallet, it'd be nice if they don't drain all the accounts based on fig…

Because in most cases you already use your card interchangeably across a wide variety of (hopefully sealed and certified) terminal devices.

Meanwhile your password is very specific to one website, and never entering it elsewhere is key to phising prevention.

(my "security domain" comment was probably worded a bit poorly with the reference to your wallet, the relevant point is that most people consider card terminals interchangeable.)

Re: Most common PIN codes (2012)

#95

Post by PawgerZ »

GoblinSlayer wrote: post #87
g4zj wrote: post #50

Before reaching the bottom of the article, I was wondering about 19xx codes, given that I've heard many people using years, or month/day pairings for garage door codes and such. I was glad to see those plotted out. I was also initially surprised that not a single 19xx pin made the top 20, but I suppose it makes sense considering that there are 100 different combinations of this code.

2000 is #7, 2001 is #19. Guess what they mean. Oh wait, it was in 2012.

Probably their child's birth year

Re: Most common PIN codes (2012)

#96

Post by eks391 »

toast0 wrote: post #56
eks391 wrote: post #44

Earlier quoted context omitted.

During tax season (in US), for security, you may optionally create a 5 digit pin. I wanted mine to be unaffiliated with any existing pin I have, and chose a 'random' number and wrote it down. A year later I repeated this (and had long since forgotten the previous pin), went to go write it in the same place, and saw that both 'random' numbers had the same first four digits. I now use a computer to choose random number…

I thought the self selected PIN for filing a return was required for online filing, and that it was just an indicator of intent, like a signature. Does it serve a security function? Am I supposed to remember what it is? I know the IRS does have an identity protection PIN process, but that's separate.

I know about the identity protection PIN, so I've been assuming this whole time that's what I was choosing a number for. It is possible I was just doing the self selected PIN and wasn't aware that I should be doing something additional for other one. FWIW I haven't needed the PIN later but saved them in case I did.
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