[VOIPSEC] Vonage To Make 911 An 'Opt-Out' Option

Bob Wise bob at bobsplanet.com
Fri May 13 17:40:26 BST 2005

When you say Vonage account server, I assume you mean their
customer/provisioning system. The call server might also be a target.


- Zombie takeover of PC with a Vonage softphone.
- DOS attack against the ATA

Candace - could you clarify the scenario you had in mind a bit?
Don't any of the attacks against a residential service disable the entire
service, not just 911? Is this a case where someone is going to say, rob
you, wants to make sure that your 911 service is disabled so you can't call
for help? If so, seems like a pretty arcane attack to me.

It DOES seem like the admin lines as you describe it are much more likely to
suffer from DOS attacks than the main call center - maybe even just normal
emergency traffic. If I have 911 service from Vonage, et. Al, sounds like
there is a much higher chance of admin line getting overrun by "normal"
traffic. Comment? 


PS: Can the moderator fix the mailman bounce processing options to deal with
the OOO messages? Thanks.

-----Original Message-----
From: Robert Moskowitz [mailto:rgm at icsalabs.com] 
Sent: Friday, May 13, 2005 8:58 AM
To: Candace Holman; Bob Wise; Voipsec at voipsa.org
Subject: RE: [VOIPSEC] Vonage To Make 911 An 'Opt-Out' Option

At 12:53 AM 5/13/2005, Candace Holman wrote:
>Some locations don't provide traditional 911 access for VoIP, it just 
>connects to an out of band administrative line at the answer point.  They 
>are supposed to make sure that the answer point is aware that emergency 
>calls may come in on that admin line.  But in terms of security, instead 
>of having to go to the trouble of snipping your phone or cable wires, with 
>this in place a criminal attacker can just hack your Vonage account to 
>disable your emergency communication line.

How does one hack a Vonage account?

I can only think of three ways:  Standard SSL MITM attacks (requires shared 
media), Keystroke capturing spyware, attacks against Vonage account 
server.  Number 2 is the most vunerable, it would seem.  And the attacker 
would typically be after things other than disabling emergency

Robert Moskowitz
Senior Technical Director
ICSA Labs, a division of Cybertrust, Inc.
W:      248-968-9809
F:      248-968-2824
VoIP:   248-291-0713
E:      rgm at icsalabs.com

There's no limit to what can be accomplished if it doesn't matter who gets 
the credit

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