Hacking attempts or iax2 error?

The log shows hundreds of below lines.
Is this a hacking attempt or an iax2 error. I don’t have a iax2 client at said IP. Should the responsive firewall catch this?

NOTICE[5888]: chan_iax2.c:8225 register_verify: Empty registration from

Look around on the internet for a whois server and get the whois information for “”. It’s probably a typo in someone’s server somewhere. Contact their admin address and let them know.

if it isn’t, you can block them in the system firewall.