Re: Yahoo! Instant Messenger

[Josh Higham <bugtraq () BIGSKY NET>]

From: Matthew Keller <kellermg () POTSDAM EDU>

> "Michael S. Fischer" wrote:
> > The third statement of this paragraph is untrue -- Almost every
transaction
> > at Yahoo! involving money uses the Yahoo! wallet system, which uses a
> > separate password from the one used by YIM and the other "standard"
> > (non-financial) services.
>
> You're assuming that the person who holds both a YIM account and a
> Wallet account uses a different password. I'd bet willing to wager that
> near five-9's of the YIM/wallet users use the same account name and
> password, thus making any disclosure of their password a problem.

That's the first thing I looked at.  Yahoo doesn't allow the passwords to be
the same (plus some other restrictions) -- I didn't actually _check_ this,
just went to the form at wallet.yahoo.com where it asks for your personal
info, and that was listed as a restriction.  However, I will agree that most
users will simply tack on an extra character, or something similar, so this
does still present a weakness.

It's pretty cool that Yahoo takes this stance on passwords, I think that
possibly searching for substrings also might be a good idea (put a big red
warning up if a 3+ character sequence matches their 'insecure' password),
but the fact remains that users will be annoyed, and they will always find a
way to choose the least secure password possible.

Josh