Phantom Calls to DDI's from random numbers

[eip1]

HI, I'm wondering if anyone has had phantom calls to DDI's that arrive every 30 seconds or so.
They appear to come from through the trunk but the SIP provider cannot see them.
The caller ID's are all random numbers and letters.
The SIP trunk is Register/Account based.
I haven't had an issue quite like this before.
PBX is OVH hosted

Thanks

Jolian

 

[leejor]

If the calls "appear" to come from your providers trunk (originate ffrom their IP, and not a direct SIP call from a random IP), then they should have a record of them. I would confirm this, and get them involved if the Invite originates with them.

Use the 3CX Activity Log for more details of the calls.

 

[eip1]

already spoken to them and they say they are not coming through the trunk and that they think they are coming directly into the PBX

 

[leejor]

If they are coming as a Direct SIP call (and I have seen hackers try that many times), then it will show the originating IP (something other than your providers) in the Activity Log.

 

[eip1]

That's what they are, random number as the originating ID

 

[leejor]

If they pass through 3CX (direct SIP to the PBX), and the originating IP is known, then the 3CX Blacklist can be used to block the IP(s), or range. Your router/firewall could also do this If they do, in fact, come in on a trunk from your provider, then you will have to ask your provider, if they are able to offer some assistance in blocking. Other than the caller ID (which you could block, if it is consistent) you will not be able to distinguish from a valid trunk call.

 

[leejor]

The 3CX Activity Log will show exactly where the calls originate if they pass through the PBX (Direct SIP call to the PBX, or coming from your provider), and are not a Direct SIP call to the set(s)

 

[eip1]

They show up in the active calls screen, the IP isn't shown anywhere. They have actually stopped as I disabled the DDI for the two affected numbers and turned off voicemail.
Been ok for a few days now...very annoying though