Re: Kazaa Sig2Dat Protocol Remote Integer Overflow and Denial Of Service by creating files in arbitrary locations

[Markus Kern <markus-kern () gmx net>]

On Tuesday, January 18, 2005, 11:59:51 PM Markus Kern <markus-kern () gmx net> wrote:

> On Monday, January 17, 2005, 9:40:47 PM Rafel Ivgi, The-Insider <theinsider () 012 net il> wrote:

> > Application:   Kazaa
> > Vendors:       http://www.kazaa.com
> > Versions:       kazaa lite k++(probably all others too...)
> > Platforms:      Windows
> > Bug:              Sig2Dat Protocol Remote Integer Overflow and
> >                      Denial Of Service by creating files in arbitrary
> > locations
> > Exploitation:   Remote With Browser
> > Date:             17 Jan 2005
> > Author:          Rafel Ivgi, The-Insider
> > E-Mail:          the_insider () mail com
> > Website:        http://theinsider.deep-ice.com

<snip toc>

> > Kazaa is currently the world’s most common P2P file sharing application.
> > When installing Kazaa a new protocol is installed named “sig2dat”.

> This is incorrect. Kazaa itself does not install a handler for the
> 'sig2dat' URIs. In fact it doesn't even know about them. The sig2dat
> URIs are created and handled by a third party tool [1] which contains
> the described flaws and happens to be included in the (unofficial)
> Kazaa Lite package.

I have to correct myself slightly here.

After closer inspection it turns out that more recent versions of
Kazaa Lite include a utility called K-Sig [2] instead of sig2dat.
K-Sig does not share any code with sig2dat. It is not clear which of
the two was used by the original poster but it seems neither of them
do any explicit filtering to prevent directory traversal attacks.

> The official Kazaa from http://www.kazaa.com does not handle sig2dat
> URIs and is not vulnerable.

> > This protocol contain an integer overflow vulnerability which may cause
> > a crash and may allow remote execution of code. There is another
> > vulnerability in the “File:” parameter which allows creating files in
> > arbitrary locations and committing Denial Of Service.

> [1] sig2dat, http://www.geocities.com/vlaibb/tools.html
>     (The design and code of this thing are horrific and there are no
>     doubt plenty of other bugs to be found)

[2] K-Sig, http://sourceforge.net/projects/hasnain

--
Markus Kern