ConfigServer Security & Firewall (CSF) LiteSpeed Configuration
If you're using ConfigServer Security & Firewall (CSF), you have to make a few changes to the CSF configuration. This guide will explain the various changes that need to be done!
Prevent Symlink Alert From LFD
In LiteSpeed Web Server version 5.3.6, we moved /tmp/lshttpd/.rtreport
to /dev/shm
to decrease disk IO. As a result, we introduced a symlink from the original location so any existing configuration doesn't break.
However, this can cause alerts from CSF/LFD such as this:
Time: Wed Feb 13 06:05:29 2019 +0100 File: /tmp/lshttpd/.rtreport Reason: Suspicious symlink (->/dev/shm/lsws/lshttpd/status/.rtreport) Owner: nobody:nobody (99:99) Action: No action taken
Add /tmp/lshttpd/\.rtreport.*
to /etc/csf/csf.fignore
to suppress this alert, and then restart CSF using csf -ra
.
Prevent LSPHP Alert From LFD
Depending on your settings, or the amount of traffic your customers receive, you can easily end up with lsphp
processes that run for a long time. This happens because we spawn a parent lsphp process for each vhost or customer. This process is used for a few things including shared memory for opcache and keeping the process alive for faster traffic handling (we skip the startup delay).
However, this can trigger some LFD alerts such as the one below:
Time: Tue Feb 12 16:33:02 2019 +0100 Account: XXXXXXXX Resource: Process Time Exceeded: 64846 > 43200 (seconds) Executable: /opt/cpanel/ea-php56/root/usr/bin/lsphp Command Line: lsphp PID: 14899 (Parent PID:14899) Killed: No
We can prevent this by adding pexe:/opt/cpanel/ea-php.*/root/usr/bin/lsphp.*
to /etc/csf/csf.pignore
, and then restarting CSF using csf -ra
.
Prevent LSHTTPD Alert From LFD
The lshttpd
binary is unknown to LFD, so you may also receive alerts like this:
Time: Tue Feb 12 19:03:40 2019 +0100 PID: 13751 (Parent PID:13739) Account: nobody Uptime: 21627 seconds Executable: /usr/local/lsws/bin/lshttpd.5.3.1 Command Line (often faked in exploits): litespeed (lshttpd - #01) Network connections by the process (if any): tcp: xx.xx.xx.xx:80 -> xx.xx.xx.xx:4007
We can prevent this by adding pexe:/usr/local/lsws/bin/lshttpd.*
to /etc/csf/csf.pignore
, and then restarting CSF using csf -ra
.
Other
If you're using QUIC, then make sure to open up port UDP 443 on your firewall. This can be done in CSF under UDP_IN
and UDP_OUT
. You can read more about enabling QUIC here.