What do the entries in kern.log and syslog AIF:(PRIV | UNPRIV) TCP packet mean? And what does it threaten?

Question

ubuntu

Hello. There is a web server under Ubuntu 14.04
There are a lot of such entries in kern.log and similar entries in syslog
: kernel: AIF:UNPRIV TCP packet: IN=eth0 OUT= MAC= SRC= DST= LEN=40 TOS=0x00 PREC=0x00 TTL=240 ID=
kernel: AIF:PRIV TCP packet: IN=eth0 OUT= MAC= SRC= DST= LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=35
kernel: AIF:ICMP-request: IN=eth0 OUT= MAC= SRC= DST= LEN=84 TOS=0x00 PREC=0x00 TTL=52 ID=0 DF
kernel: AIF:UNPRIV TCP packet: IN=eth0 OUT= MAC= SRC= DST= LEN=60 TOS=0x00 PREC =0x00 TTL=58 ID=
What do they mean?
Do I need to do something about it?
Why is this "terrible" for the web server and, accordingly, the site?
I can assume that these entries are somehow related to changes insysctl.conf or with arno iptables firewall , but what to change, analyze, where to look? I don't understand any of this, that's why I'm asking.

Answer 1

AIF stands for " Arno's iptables-firewall" . UNPRIV means that AIF has detected a call to a destination port higher than 1024. That is, the presence of such entries is related to arno iptables firewall .
But to say what to do with it, and whether it is necessary to do something at all, from the information given in the question is not possible.