Ensure permissions on /etc/passwd are configured

MediumLevel 1Automatedfreebsd

Description

The /etc/passwd file contains user account information used by many system utilities, which must be readable for these utilities to operate. It is critical to ensure that the /etc/passwd file is protected from unauthorized write access. Although it is protected by default, the file permissions could be changed inadvertently or through malicious actions. 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/passwd; 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: $s"; else r="$f: missing"; fi; done; echo "$r"

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Run the following commands to remove excess permissions, set owner, and set group on /etc/passwd: # chmod u-x,go-wx /etc/passwd # chown root:root /etc/passwd

Properties

Operating systems: Any
Tags: freebsdpermissions
Reference: CIS FreeBSD 14 Benchmark v1.0.1 - 6.1.1 Ensure permissions on /etc/passwd are configured

Check this host

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

shell

tmaegis scan --target freebsd