Re: Cantv/Movilnet's Web SMS vulnerability.

Bugtraq @ SNSecurity wrote:
> Quick Summary:
> ************************************************************************
>
> Product : Movilnet's Web SMS.
> Version : In-production versions.
> Vendor : Movilnet - http://www.movilnet.com.ve/
> Class : Remote
> Criticality : High
> Operating System(s) : N/A.
[snip]
> Proof Of Concept Status
> ************************************************************************
>
> No proof of Concept will be released until the provider has sorted out 
> the
> issue.
A first impact Proof of Concept is to use imagemagick tools with gocr to 
have a good image.
I've used colors level input: 31 0.11 160 (you can use gimp too to see 
the effects) to have a white background and black (or most like black 
:P) foreground.
Later i've used gocr with djpeg in pipe (see gocr -h to understand 
better) and i've obtained the famous number.
I've already writed a perl software to send sms to cantv mobiles and not 
is soo hard to implement this last operations, but not is public this 
latest version because i do for myself.

> Credits
> ************************************************************************
>
> This vulnerability was discovered by Ruben Recabarren and Leandro 
> Leoncini
> at SNSecurity's Research Lab.
Good work, to the advisors. But i think that everyone that have a not so 
insane mind can understand the CanTv stupidity of this captcha 
implementation.