Re: VoIP pentest ?

[Mark Teicher <mht3 () earthlink net>]

Actually, the question for VOIP pen-testing should be split into two issues:

1. How many vulnerable is a network with VOIP ?
2. Is the network ready for VOIP?
3. VOIP Attack suite

1. Here is the tricky part,  most saavy security consultants will apply 
normal security methodology techniques in examining a network using <insert 
your favorite network topology mapping tool> and < insert your favorite 
network scanning tools> to assess the network.  In a previous life, I 
worked with a Phd who didn't want to listen that wrote some a methodology 
for security assessments, only a minimum of what he wrote applies in 
examining a network with VoIP.

2. Is a network ready for VOIP?  That is an interesting question since most 
<insert you favorite scanning tool here> will provide an organization or 
security consultants very minimal information on whether a network is ready 
for VOIP.  WARNING: If a security consultant who offers a VOIP readiness 
check, inquire what tools they use, if their answer begins with <insert 
your favorite network scanning tool>, be very afraid.

3.  VOIP Attack suite - there are rudimentary scanning tools out there for 
assessing VOIP products, but does not encompass all the components of a 
VOIP setup.  Here is the issue, running a scan across IP phones will cause 
users of a particular organization get a little miffed, since most IP 
phones do not have denial of service protection built-in, so that is 
out.  Another issue is that most common intrusion detection systems have 
not incorporated VOIP protocol decodes into their products yet, there are a 
couple of pattern matching signatures out there for Sn0rt but very few, so 
at most, when running VOIP attacks on a VOIP network, the majority of noise 
will be from the users and very little information will be gathered about 
the VOIP products except OS banner collection, and port flapping.

hope this helps

/m


At 08:32 AM 10/28/2004, Volker Tanger wrote:

> Greetings!
>
> On Wed, 27 Oct 2004 11:28:51 +0200 Frederic Charpentier
> <fcharpen () xmcopartners com> wrote:
> > does anyone have experiences or papers on VoIP pentest/assessment ?
> > Expecting classic OS/Network audits and H323/ASN.1 flaws, I can't find
> > any documentations or papers about flaws in VoIP architecture.
>
> VoIP (SIP and H.323) do media transfer via (unencrypted) RTP/RTCP.
> SIP is a simple, unauthenticated cleartext protocol. H.323 similar
> (binary and more complex, but still unauthenticated).
>
> With ARPspoofing etc. it is simple to listen to voice streams or call
> setup - or change it. So re-routing voice streams or calls should be
> simple.
>
> Quite a high percentage of systems were/are susceptible to buffer
> overflows it seems (forgot the URL - about half a year ago).
>
> For other fun with SIP see e.g.
> http://www.infoanarchy.org/story/2004/9/15/23127/3363
>
> Bye
>
> Volker Tanger
> ITK Security