Re: Randomness Attacks Against PHP Applications

[Josh Bressers <bressers () redhat com>]

----- Original Message -----
> On Wed, Aug 22, 2012 at 02:31:07PM +0400, Solar Designer wrote:
> > On Thu, Aug 09, 2012 at 11:19:14AM -0700, Yves-Alexis Perez wrote:
> > > Paper authors tried to port this to PHP security team, but it seems
> > > the answer was that it was an application problem.
> >
> > Here's a vulnerability in and attack on session IDs of PHP proper:
> >
> > http://blog.ptsecurity.com/2012/08/not-so-random-numbers-take-two.html
> >
> > This is not exactly the same topic (PHP apps vs. PHP itself), yet it's
> > closely related and the timing of it was provoked by the same research.
>
> FWIW, here's a PHP mt_rand() seed cracker that I wrote:
>
> http://download.openwall.net/pub/projects/php_mt_seed/
>
> It finds possible seeds given the very first mt_rand() output after
> being seeded with mt_srand().

...

> Maybe these PoCs will help convince someone.

I'm skeptical they will. I've been doing a lot of work for the past year on
various proactive security efforts. I keep coming back to two basic things.

1) Most people don't understand security (if they can learn is another
topic).
2) We suck at explaining security concepts.

Item 1 is solvable to a certain degree with training, but this particular
issue I bet is #2.

WE see why this is a problem and have trouble understanding why the PHP
guys don't. Has anyone tried to talk to them about this further to see if
the issue is they don't understand, or are they being stubborn?

I'm quite interested in this problem (the general communication issue, not
specially this PHP problem).

Thanks.

-- 
    JB