Random internal calls

[MartinBonnici]

Hi all,

we keep getting random internal calls on our 3CX system - some of them truly weird like extension 900 calling extension 900. They do not show up in the call logs and can either be 10 calls a day or nothing for a week. Any idea of what this could be?

We mostly use soft phones, but we also have a Grandstream desk phone and a Yealink and they are the main culprits. However we've also had some similar activities between softphones on Android and iOS.

Any help would be greatly appreciated

 

[Alphabetic]

Sounds like ghost calls. Are your phones and PBX in the same LAN or are they STUN?

Is your SIP port open on the firewall?

 

[MartinBonnici]

The PBX is cloud hosted and the phones are split between two offices. I believe the hardphones were setup via STUN.

As for the firewall, I'm running a firewall test on the 3CX interface now. Do you think we need to make a ritual sacrifice to get our system rid of ghosts or is it more likely to be some hacking attempts?

 

[Alphabetic]

The problem will on the firewall at your sites.

Have you opened the phone SIP ports at each site to go to the respected phone?

If so, did you lock it down to only the WAN IP of your PBX?

 

[MartinBonnici]

Ah that I do not know as we had a service provider handle installations. So it could be from that?

 

[Alphabetic]

Yes, it's more then likely you have the port open on your firewall.

I'd start using the SBC on a Pi - So much easier and less hassle than STUN.