Block SIP Authentication Attacks with nftables
If you’re running a SIP-based PBX system (Asterisk, FreeSWITCH, FreePBX, MikoPBX, etc.) exposed to the internet, you’re likely seeing constant authentication attacks from bots scanning for vulnerable systems. In my previous article on blocking SIP attacks with iptables, I showed you how to use hostname-based filtering to stop these attacks before they reach your PBX….
