I have an Asterisk PBX configured at a client. I used the FreePBX Distro for a quick set-up. Everything on the box is fully up-to-date.
The client is only a single guy with a single phone. The phone is configured on extension 201, the only extension on the box. Still, there are about 10 - 20 calls/hour going out with CID’s that are not even configured on the box (4-digits, 7 digits, ‘admin11’, etc…). CDRs show “s [from-sip-external]” as destination. The firewall is as tight as possible on both the box and the router. On the router, only a range of 30 ports is opened for RTP voice signalling. 5060 is closed as well as all other ports.
How is this possible? I have a vague idea this could caused by the way I configured the dial plan. I only have one rule with just a dot “.” to allow all calls through.
Anyone got an idea? Thanks a million in advance.