Strange calls

I have these strange calls beetween th normal ones

777 and 101 are not extensions in the PBX.

What are these calls??

Here are the flow of them

If you allow anonymous/guest calls and don’t have a properly configured firewall/ids then you will see these.

Plenty of posts here and recipes on google to protect yourself.

Thanks Dicko i disallowed anonymous calls in SIP settings.

But i still got that calls

You need to not all guest calls as well.