View previous topic :: View next topic |
Author |
Message |
erg_samowzbudnik Apprentice
Joined: 09 Sep 2011 Posts: 229 Location: European sticks
|
Posted: Tue Mar 21, 2023 5:15 pm Post subject: firewall, sshguard and interpretting log files |
|
|
Hi.
I have network consisting of router (OpenWrt) filtering incoming traffic on all but few ports and forwarding it to Raspberry Pi running Gentoo.
On RPi I have sshd and sshguard running.
I should think traffic to ports that are restricted by firewall on the router shouldn't appear in logs on RPi but it does: I see attacks on ssh coming on various ports.
But when I fire up tcpdump on RPI and try to get through the firewall that traffic does not arrive to RPi.
What gives?
This sample of logs: Code: | Mar 21 18:01:36 pie sshd[21335]: Received disconnect from 8.213.25.141 port 53910:11: Bye Bye [preauth]
Mar 21 18:01:36 pie sshd[21335]: Disconnected from authenticating user root 8.213.25.141 port 53910 [preauth]
Mar 21 18:01:36 pie sshguard[2291]: Attack from "8.213.25.141" on service SSH with danger 10.
Mar 21 18:01:36 pie sshguard[2291]: Attack from "8.213.25.141" on service SSH with danger 10 |
Do I read the second line here correctly and attack came in on port 53910?
What are those numbers after sshd[21355] and sshguard[2291]?
I use ssh keys, but noise in logs is most annoying. |
|
Back to top |
|
|
pingtoo Veteran
Joined: 10 Sep 2021 Posts: 1472 Location: Richmond Hill, Canada
|
Posted: Tue Mar 21, 2023 5:40 pm Post subject: |
|
|
erg_samowzbudnik,
On you OpenWRT box, does it have "iptables" command? if it does please share output of Please review the output before post and mask out any sensitive data.
erg_samowzbudnik wrote: | when I fire up tcpdump on RPI and try to get through the firewall that traffic does not arrive to RPi. | My guess, could it possible you used a wrong device for your tcpdump?
So do you think your sshguard is working? as in the attack messages only show very few times. (because sshguard block it) Or sshguard is not work? as in you continue seeing the attack messages? |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
|