The Phone is Ringing

Friday, December 11, 2009, at 07:25PM

By Eric Richardson

Breaking with today's trends, Kathy and I have a home phone. It's not something that we really ever use and it's probably a waste of money to have it, but it's just a few dollars a month and was an easier option than deciding that the building call box would ring to my cell phone.

Seeing how much I love over-designed and half-implemented solutions, it shouldn't surprise that this phone is a VoIP handset that connects to an Asterisk server and an Adhearsion dial plan app.

What is a surprise is that over the last 24 hours, the phone's been ringing at the oddest hours.

In fact, it rang at 2:21am, 4:57am, 6:01am, 7:15am and 8:36pm. Instead of a caller ID number, the handset shows "sip" and "asterisk."

The last bit is the key that these aren't just wrong numbers or robo-calls. Instead, they are calls coming in via direct SIP connections to the Asterisk server.

Frankly, I hadn't even considered that a possibility. Who randomly dials IP addresses looking for phone systems?

The first connection arrived via, an IP address in Virginia. Three calls were placed, trying to ring "extensions" of 00442086371406, 0442086371406 and 000442086371406.

The second came via and, both IPs in China. They attempted to dial 003318288029, 00033182880295 and 033182880295.

The third came via, an IP in Romania. Again, three calls, this time to 00442073942500, 0442073942500 and 000442073942500.

What to make of these? Apparently, there are people / scripts out there war-dialing IPs looking for asterisk installs that are mis-configured to allow arbitrary connections to dial out. They're hoping to use these installs to place international calls.

My setup isn't one of those, though it probably shouldn't be allowing random IPs to connect, either. Perhaps it's time to button that up.

For now, though, I'm just curious what would be there if I actually answered one of those calls.