FreePBX Distro 10.13.66-17 with Asterisk 13 updated to 17 the day it was released. All modules are up to date as well and I am running the integrated firewall.
We see thousands of lines like below in /var/log/messages followed by what appears to be a reboot, followed by thousands more lines of that. Blocking the src ip in the firewall does not work. Our hosting provider thinks it’s a kernel vulnerability but we checked and the kernel is up to date as per the 10/29 update.
I think it is an iptables rule set to log invalid SIP traffic. If you are adding the firewall rule after this one then you will still see it in the syslog.
I think the thousands of messages (one every second) are putting extra load on the server and it gets to the point where it hangs and reboots (my sysctl.conf reboots a hung server after 300 seconds)
I doubt it. One syslog message per second is not really any load at all. But if you want to eliminate it then find the iptables rule that is doing the logging and delete it.
Based on the logs and description you’ve posted here, no. Look for other reasons your server is hanging. I would not worry about this logging, but if you are concerned, use iptables -L -n --line-numbers to find the logging rule and then use iptables -D ... with the chain and line number of the logging rule in order to stop it, temporarily, until the next restart or if the firewall rules are reloaded.