3CX Shared Hosting - Blocked
Crazytel has been left with no choice but to block the IP addresses of 3CX SMB multi-tenant cloud hosted servers on the Crazytel network.
This is a network-wide block. Registrations and calls from those shared 3CX hosting IPs will no longer be accepted on our network.
Why we have taken this step
3CX's shared SMB cloud hosting is a multi-tenant platform. Many customers sit behind the same public IP addresses. That shared setup is being exploited by fraud and scam operators.
Because legitimate customers and bad actors share the same IPs, we cannot stop the abuse without also blocking the hosting platform itself.
The scams we have been seeing
Over the last few months, the abuse coming through this shared hosting has included very serious scams. These are organised fraud operations targeting people in Australia and the UK, not low-level nuisance calls.
The main patterns we have been dealing with include:
- Crypto scams - callers using the shared 3CX platform as part of cryptocurrency fraud.
- Commonwealth Bank impersonation scams - callers pretending to be from Commonwealth Bank to trick people into handing over banking details or funds.
- UK bank impersonation scams - callers pretending to be from UK banks to steal banking details or funds.
These scams have been serious enough that we can no longer leave this shared hosting platform reachable on our network.
What we have already tried
We have previously worked with 3CX to stop this abuse. Those efforts have not produced a solution we can rely on. With no workable way to separate fraudulent traffic from the rest of that shared service, we have applied a network-wide block.
Who this affects
This block applies to 3CX SMB multi-tenant / shared cloud hosting only. It targets the shared public IPs used by that hosted service.
If you run 3CX on your own server, or on a dedicated instance with its own IP address, this block is not aimed at you.
What to do if you are affected
If your 3CX system is on 3CX's shared SMB cloud hosting and you use Crazytel SIP trunks, those trunks will no longer register or send calls through that hosted platform.
You will need to move off the shared hosting platform - for example to a self-hosted or dedicated 3CX instance - before those trunks will work again. If you need help working out what this means for your service, contact Crazytel support.
