I received a fraud alert from our SIP provider telling us that someone was using one of our numbers to make calls. I'm not seeing this activity on our Adtran. I have SMDR logging turned on but i still am not seeing the activity they are describing. How can i determine where the vulnerability may exist?
The only way someone can do this remotely is if they register a softphone to your 7100 and then place calls out from there. The only way this is possible is if your firewall is not configured properly.
What is your PSTN connection? Sip/PRI/Analog?
Can you send us your firewall configuration in running config.