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|
#!/bin/sh
#################################################################################
#
# Lynis
# ------------------
#
# Copyright 2007-2013, Michael Boelen
# Copyright 2007-2021, CISOfy
#
# Website : https://cisofy.com
# Blog : http://linux-audit.com
# GitHub : https://github.com/CISOfy/lynis
#
# Lynis comes with ABSOLUTELY NO WARRANTY. This is free software, and you are
# welcome to redistribute it under the terms of the GNU General Public License.
# See LICENSE file for usage of this software.
#
#################################################################################
#
# Scheduled tasks
#
#################################################################################
#
InsertSection "${SECTION_SCHEDULED_TASKS}"
#
#################################################################################
#
ATD_RUNNING=0
CROND_RUNNING=0
#
#################################################################################
#
# Test : SCHD-7702
# Description : Check cron daemon
Register --test-no SCHD-7702 --weight L --network NO --category security --description "Check status of cron daemon"
if [ ${SKIPTEST} -eq 0 ]; then
FIND=$(${PSBINARY} aux | ${EGREPBINARY} "( cron$|/cron(d)? )")
if IsEmpty "${FIND}"; then
LogText "Result: no cron daemon found"
else
LogText "Result: cron daemon running"
CROND_RUNNING=1
Report "crond_running=1"
Report "scheduler[]=crond"
fi
fi
#
#################################################################################
#
# Test : SCHD-7704
# Description : Check crontab / cronjobs
Register --test-no SCHD-7704 --weight L --network NO --category security --description "Check crontab/cronjobs"
if [ ${SKIPTEST} -eq 0 ]; then
BAD_FILE_PERMISSIONS=0
BAD_FILE_OWNERSHIP=0
FindCronJob() {
sCRONJOBS=$(${EGREPBINARY} '^([0-9*])' $1 | ${TRBINARY} '\t' ' ' | ${TRBINARY} -s ' ' | ${TRBINARY} ' ' ',' | ${SORTBINARY})
}
CRONTAB_FILE="${ROOTDIR}etc/crontab"
if [ -f ${CRONTAB_FILE} ]; then
${EGREPBINARY} -q -s 'lynis audit system' ${CRONTAB_FILE} && LYNIS_CRONJOB="file:/etc/crontab"
if IsWorldWritable ${CRONTAB_FILE}; then LogText "Result: insecure file permissions for cronjob file ${CRONTAB_FILE}"; Report "insecure_fileperms_cronjob[]=${CRONTAB_FILE}"; BAD_FILE_PERMISSIONS=1; AddHP 0 5; fi
if ! IsOwnedByRoot ${CRONTAB_FILE}; then LogText "Result: incorrect owner found for cronjob file ${CRONTAB_FILE}"; Report "bad_fileowner_cronjob[]=${CRONTAB_FILE}"; BAD_FILE_OWNERSHIP=1; AddHP 0 5; fi
FindCronJob ${CRONTAB_FILE}
for ITEM in ${sCRONJOBS}; do
LogText "Found cronjob (${CRONTAB_FILE}): ${ITEM}"
Report "cronjob[]=${ITEM}"
done
fi
CRON_DIRS="${ROOTDIR}etc/cron.d"
for DIR in ${CRON_DIRS}; do
LogText "Test: checking directory ${DIR}"
if [ -d ${DIR} ]; then
if FileIsReadable ${DIR}; then
LogText "Result: found directory ${DIR}"
LogText "Test: searching files in ${DIR}"
FIND=$(${FINDBINARY} -L ${DIR} -type f -print | ${GREPBINARY} -v ".placeholder")
if IsEmpty "${FIND}"; then
LogText "Result: no files found in ${DIR}"
else
LogText "Result: found one or more files in ${DIR}. Analyzing files.."
for FILE in ${FIND}; do
if IsWorldWritable ${FILE}; then LogText "Result: insecure file permissions for cronjob file ${J}"; Report "insecure_fileperms_cronjob[]=${J}"; BAD_FILE_PERMISSIONS=1; AddHP 0 5; fi
if ! IsOwnedByRoot ${FILE}; then LogText "Result: incorrect owner found for cronjob file ${J}"; Report "bad_fileowner_cronjob[]=${J}"; BAD_FILE_OWNERSHIP=1; AddHP 0 5; fi
FILENAME=$(echo ${FILE} | ${AWKBINARY} -F/ '{print $NF}')
if [ "${FILENAME}" = "lynis" ]; then ${EGREPBINARY} -q -s 'lynis audit system' ${CRONTAB_FILE} && LYNIS_CRONJOB="file:${FILE}"; fi
FindCronJob ${FILE}
if HasData "${sCRONJOBS}"; then
for K in ${sCRONJOBS}; do
LogText "Result: Found cronjob (${FILE}): ${K}"
Report "cronjob[]=${FILE}"
done
fi
done
LogText "Result: done with analyzing files in ${DIR}"
fi
else
LogText "Result: can not read file or directory ${DIR}"
fi
else
LogText "Result: directory ${DIR} does not exist"
fi
done
CRON_DIRS="${ROOTDIR}etc/cron.hourly ${ROOTDIR}etc/cron.daily ${ROOTDIR}etc/cron.weekly ${ROOTDIR}etc/cron.monthly"
for I in ${CRON_DIRS}; do
LogText "Test: checking directory ${I}"
if [ -d ${I} ]; then
LogText "Result: found directory ${I}"
if FileIsReadable ${I}; then
LogText "Test: searching files in ${I}"
FIND=$(${FINDBINARY} -L ${I} -type f -print 2> /dev/null | ${GREPBINARY} -v ".placeholder")
if [ -z "${FIND}" ]; then
LogText "Result: no files found in ${I}"
else
LogText "Result: found one or more files in ${I}. Analyzing files.."
for FILE in ${FIND}; do
if IsWorldWritable ${FILE}; then LogText "Result: insecure file permissions for cronjob file ${FILE}"; Report "insecure_fileperms_cronjob[]=${FILE}"; BAD_FILE_PERMISSIONS=1; AddHP 0 5; fi
if ! IsOwnedByRoot ${FILE}; then LogText "Result: incorrect owner found for cronjob file ${FILE}"; Report "bad_fileowner_cronjob[]=${FILE}"; BAD_FILE_OWNERSHIP=1; AddHP 0 5; fi
FILENAME=$(echo ${FILE} | ${AWKBINARY} -F/ '{print $NF}')
if [ "${FILENAME}" = "lynis" ]; then ${EGREPBINARY} -q -s 'lynis audit system' ${CRONTAB_FILE} && LYNIS_CRONJOB="file:${FILE}"; fi
LogText "Result: Found cronjob (${I}): ${FILE}"
Report "cronjob[]=${FILE}"
done
LogText "Result: done with analyzing files in ${I}"
fi
else
LogText "Result: directory permissions are too strict to enter it (which might be good)"
fi
else
LogText "Result: directory ${I} does not exist"
fi
done
# /var/spool/cron/* and /var/spool/cron/crontabs/*
# Search only in one tree, to avoid searching the tree twice
if [ -d /var/spool/cron/crontabs ]; then
FIND=$(${FINDBINARY} /var/spool/cron/crontabs -xdev -type f -print 2> /dev/null)
for I in ${FIND}; do
if FileIsReadable ${I}; then
${EGREPBINARY} -q -s 'lynis audit system' ${I} && LYNIS_CRONJOB="file:${I}"
FindCronJob ${I}
for FILE in ${sCRONJOBS}; do
LogText "Found cronjob (/var/spool/cron/crontabs): ${I} (${FILE})"
Report "cronjob[]=${I}"
done
fi
done
else
if [ -d ${ROOTDIR}var/spool/cron ]; then
FIND=$(find ${ROOTDIR}var/spool/cron -type f -print)
for I in ${FIND}; do
if FileIsReadable ${I}; then
${EGREPBINARY} -q -s 'lynis audit system' ${I} && LYNIS_CRONJOB="file:${I}"
FindCronJob ${I}
for FILE in ${sCRONJOBS}; do
LogText "Found cronjob in ${ROOTDIR}var/spool/cron: ${I} (${FILE})"
LogText "cronjob[]=${I}"
done
fi
done
fi
fi
# Anacron
if [ "${OS}" = "Linux" ]; then
if [ -f /etc/anacrontab ]; then
LogText "Test: checking anacrontab"
sANACRONJOBS=$(${EGREPBINARY} '^([0-9@])' /etc/anacrontab | ${TRBINARY} '\t' ' ' | ${TRBINARY} -s ' ' | ${TRBINARY} ' ' ',' | ${SORTBINARY})
if [ -n "${sANACRONJOBS}" ]; then
Report "scheduler[]=anacron"
for I in ${sANACRONJOBS}; do
LogText "Found anacron job (/etc/anacrontab): ${I}"
Report "cronjob[]=${I}"
done
fi
fi
fi
# Show warning when an issue shows up. Even if *both* the permissions and ownership are wrong, just show one (prevent overload of warnings).
if [ ${BAD_FILE_PERMISSIONS} -eq 1 ]; then
ReportWarning "${TEST_NO}" "Found one or more cronjob files with incorrect file permissions (see log for details)"
Display --indent 2 --text "- Checking crontab and cronjobs files" --result "${STATUS_WARNING}" --color RED
elif [ ${BAD_FILE_OWNERSHIP} -eq 1 ]; then
ReportWarning "${TEST_NO}" "Found one or more cronjob files with incorrect ownership (see log for details)"
Display --indent 2 --text "- Checking crontab and cronjob files" --result "${STATUS_WARNING}" --color RED
else
Display --indent 2 --text "- Checking crontab and cronjob files" --result "${STATUS_DONE}" --color GREEN
fi
fi
#
#################################################################################
#
# Test : SCHD-7718
# Description : Check atd status
Register --test-no SCHD-7718 --weight L --network NO --category security --description "Check at users"
if [ ${SKIPTEST} -eq 0 ]; then
LogText "Test: Checking atd status"
FIND=$(${PSBINARY} ax | ${GREPBINARY} "/atd" | ${GREPBINARY} -v "grep")
if [ -n "${FIND}" ]; then
LogText "Result: at daemon active"
Display --indent 2 --text "- Checking atd status" --result "${STATUS_RUNNING}" --color GREEN
ATD_RUNNING=1
Report "scheduler[]=atd"
else
LogText "Result: at daemon not active"
if IsVerbose; then Display --indent 2 --text "- Checking atd status" --result "${STATUS_NOT_RUNNING}" --color WHITE; fi
fi
fi
#
#################################################################################
#
# Test : SCHD-7720
# Description : Check at users
# Notes : if at.allow exists, only users listed can schedule at jobs
# if at.allow does not exist, but at.deny does, everyone
# except the listed ones can schedule jobs. If both can't be
# found, only root can schedule jobs.
if [ ${ATD_RUNNING} -eq 1 ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no SCHD-7720 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check at users"
if [ ${SKIPTEST} -eq 0 ]; then
AT_UNKNOWN=0
case ${OS} in
FreeBSD) AT_ALLOW="${ROOTDIR}var/at/at.allow"; AT_DENY="${ROOTDIR}var/at/at.deny" ;;
HPUX) AT_ALLOW="${ROOTDIR}usr/lib/cron/at.allow"; AT_DENY="${ROOTDIR}usr/lib/cron/at.deny" ;;
Linux) AT_ALLOW="${ROOTDIR}etc/at.allow"; AT_DENY="${ROOTDIR}etc/at.deny" ;;
OpenBSD) AT_ALLOW="${ROOTDIR}var/cron/at.allow"; AT_DENY="${ROOTDIR}var/cron/at.deny" ;;
SunOS) AT_ALLOW="${ROOTDIR}etc/cron.d/at.allow"; AT_DENY="${ROOTDIR}etc/cron.d/at.deny" ;;
*) AT_UNKNOWN=1; LogText "Test skipped, files for at unknown" ;;
esac
if [ ${AT_UNKNOWN} -eq 0 ]; then
LogText "Test: checking for file ${AT_ALLOW}"
if [ -f ${AT_ALLOW} ]; then
FileIsReadable ${AT_ALLOW}
if [ ${CANREAD} -eq 1 ]; then
LogText "Result: file ${AT_ALLOW} exists, only listed users can schedule at jobs"
FIND=$(${SORTBINARY} ${AT_ALLOW})
if IsEmpty "${FIND}"; then
LogText "Result: File empty, no users are allowed to schedule at jobs"
else
for ITEM in ${FIND}; do
LogText "Allowed at user: ${ITEM}"
done
fi
else
LogText "Result: can not read ${AT_ALLOW} (no permission)"
fi
else
LogText "Result: file ${AT_ALLOW} does not exist"
LogText "Test: checking for file ${AT_DENY}"
if [ -f ${AT_DENY} ]; then
FileIsReadable ${AT_DENY}
if [ ${CANREAD} -eq 1 ]; then
LogText "Result: file ${AT_DENY} exists, only non listed users can schedule at jobs"
FIND=$(${SORTBINARY} ${AT_DENY})
if [ -z "${FIND}" ]; then
LogText "Result: file is empty, no users are denied access to schedule jobs"
else
for ITEM in ${FIND}; do
LogText "Denied at user: ${ITEM}"
done
fi
else
LogText "Result: can not read ${AT_DENY} (no permission)"
fi
else
LogText "Result: both ${AT_ALLOW} and ${AT_DENY} do not exist"
LogText "Note: only root can schedule at jobs"
AddHP 1 1
fi
fi
Display --indent 4 --text "- Checking at users" --result "${STATUS_DONE}" --color GREEN
else
Display --indent 4 --text "- Checking at users" --result "${STATUS_SKIPPED}" --color YELLOW
fi
fi
#
#################################################################################
#
# Test : SCHD-7724
# Description : Check scheduled at jobs
if [ ${ATD_RUNNING} -eq 1 ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no SCHD-7724 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Check at jobs"
if [ ${SKIPTEST} -eq 0 ]; then
LogText "Test: Check scheduled at jobs"
FIND=$(atq | ${GREPBINARY} -v "no files in queue" | ${AWKBINARY} '{gsub("\t"," ");print}' | ${SEDBINARY} 's/ /!space!/g')
if HasData "${FIND}"; then
LogText "Result: found one or more jobs"
for ITEM in ${FIND}; do
VALUE=$(echo ${ITEM} | ${SEDBINARY} 's/!space!/ /g')
LogText "Found at job: ${VALUE}"
done
Display --indent 4 --text "- Checking at jobs" --result "${STATUS_FOUND}" --color GREEN
else
LogText "Result: no pending at jobs"
Display --indent 4 --text "- Checking at jobs" --result "${STATUS_NONE}" --color GREEN
fi
fi
#
#################################################################################
#
if [ -z "${LYNIS_CRONJOB}" ]; then
LogText "Result: no scheduled Lynis execution found (e.g. crontab, cronjob)"
else
LogText "Result: found scheduled Lynis execution (${LYNIS_CRONJOB})"
fi
WaitForKeyPress
#
#================================================================================
# Lynis - Security Auditing and System Hardening for Linux and UNIX - https://cisofy.com
|
