voice gateway system is hacked and make many toll calls

[tinafaye87796]

I am a newbie in cisco internal audit.

our company voice gateway system is hacked and make many toll calls.

I found our internet gateway router (cisco 3925)has a unknown suspicious username and some ip local pool...

we are auditing the system. I am quite confused how our system is hacked. may anyone can help? my questions are:

1. How a hacker can create a account in my internet gateway router ? any known Vulnerability?
2. Why the hacker use the vpn ?
3. How hacker can instruct the voice gateway after login the internet router?

THX!

Best regards,

Tina

[balaji.bandi]

it all depends on your setup and how you secured your dial plan.

[George Sotiropoulos]

It is really important to fain knowledge on network segmentation and security. To answer your questions, someone should know your environment (in terms of networking) but also your dial-plan.

George