TMA-FREEBSD-1.6.4

Ensure access to /etc/motd is configured

LowLevel 1Automatedfreebsd

Description

The contents of the /etc/motd file are displayed to users after login and function as a message of the day for authenticated users. -IF- the /etc/motd file does not have the correct access configured, it could be modified by unauthorized users with incorrect or misleading information. Audit: compares `ls -ld` mode (this mode or more restrictive), owner and group with the CIS values.

How it is checked

Audit method: Shell command

shell

r=compliant; for f in /etc/motd; do if [ -e "$f" ]; then set -- $(ls -ld "$f"); s=$(printf '%s %s %s\n' "$1" "$3" "$4" | awk -v m='rw-r--r--' -v o='root' -v g='wheel' '{ok=1; for(i=1;i<=9;i++) if(substr(m,i,1)=="-" && substr($1,i+1,1)!="-") ok=0; if(o!="" && $2 !~ ("^(" o ")$")) ok=0; if(g!="" && $3 !~ ("^(" g ")$")) ok=0; print (ok ? "ok" : $0)}'); [ "$s" = ok ] || r="$f: $s"; else :; fi; done; echo "$r"

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Run the following commands to set mode, owner, and group on /etc/motd: # chown root:wheel $(readlink -f /etc/motd) # chmod u-x,go-wx $(readlink -f /etc/motd) -OR- Run the following command to remove the /etc/motd file: # rm /etc/motd

Properties

Operating systems: Any
Tags: freebsdpermissions
Reference: CIS FreeBSD 14 Benchmark v1.0.1 - 1.6.4 Ensure access to /etc/motd is configured

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target freebsd