A Nagios check for FreeBSD systems which have https://www.freshports.org/ports-mgmt/pkg installed

periodic.conf

# I use these settings in /etc/periodic.conf
# for security/405.pkg-base-audit and others
security_status_baseaudit_enable="YES"
security_status_baseaudit_jails="*"
security_status_pkgaudit_expiry=1
pkg_jails='*'

pkg-audit.sh

#!/bin/sh

SUDO="/usr/local/bin/sudo"

PKG_AUDIT="/usr/local/etc/periodic/security/410.pkg-audit"

RESULT=`${SUDO} ${PKG_AUDIT} 2>&1`
CODE=$?

if [ "${CODE}" == "0" ]
then
  echo 'No problems found'
  exit 0
else
  echo ${RESULT}
  exit 2
fi

see also https://gist.github.com/dlangille/bc9ae5b2bd37e1301cddd5d56a93da40