#!/bin/sh
#################################################################################
#
# Lynis
# ------------------
#
# Copyright (c) Michael Boelen, CISOfy, and many contributors.
#
# Website : https://cisofy.com
# Blog : https://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.
#
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#
# Home directories
#
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#
InsertSection "${SECTION_HOME_DIRECTORIES}"
#
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#
# Ignore some top level directories (not the sub directories below)
IGNORE_HOME_DIRS="/bin /boot /cdrom /dev /etc /home /lib /lib64 /media /mnt
/opt /proc /sbin /selinux /srv /sys /tmp /usr /var"
#
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#
# Test : HOME-9302
# Description : Create list with home directories
Register --test-no HOME-9302 --weight L --network NO --category security --description "Create list with home directories"
if [ ${SKIPTEST} -eq 0 ]; then
# Read sixth field of /etc/passwd
LogText "Test: query ${ROOTDIR}etc/passwd to obtain home directories"
FIND=$(${AWKBINARY} -F: '{ if ($1 !~ "#") print $6 }' ${ROOTDIR}etc/passwd | ${SORTBINARY} -u)
for I in ${FIND}; do
if [ -d ${I} ]; then
LogText "Result: found home directory: ${I} (directory exists)"
Report "home_directory[]=${I}"
else
LogText "Result: found home directory: ${I} (directory does not exist)"
fi
done
fi
#
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#
# Test : HOME-9304
# Description : Check if users' home directories permissions are 750 or more restrictive
Register --test-no HOME-9304 --weight L --network NO --category security --description "Check if users' home directories permissions are 750 or more restrictive"
if [ ${SKIPTEST} -eq 0 ]; then
# Check if users' home directories permissions are 750 or more restrictive
FOUND=0
USERDATA=$(${GREPBINARY} -E -v '^(daemon|git|halt|root|shutdown|sync)' ${ROOTDIR}etc/passwd | ${AWKBINARY} -F: '($7 !~ "/(false|nologin)$") { print }')
while read -r LINE; do
USER=$(echo ${LINE} | ${CUTBINARY} -d: -f1)
DIR=$(echo ${LINE} | ${CUTBINARY} -d: -f6)
LogText "Test: checking directory '${DIR}' for user '${USER}'"
if [ -d "${DIR}" ]; then
WRITE_GROUP_PERM=$(${LSBINARY} -ld ${DIR} | ${CUTBINARY} -f1 -d" " | ${CUTBINARY} -c6)
OTHER_PERMS=$(${LSBINARY} -ld ${DIR} | ${CUTBINARY} -f1 -d" " | ${CUTBINARY} -c8-10)
if [ ! ${WRITE_GROUP_PERM} = "-" -o ! ${OTHER_PERMS} = "---" ]; then
LogText "Result: permissions of home directory ${DIR} of user ${USER} are not strict enough. Should be 750 or more restrictive. Change with: chmod 750 ${DIR}"
FOUND=1
else
LogText "Result: permissions of home directory ${DIR} of user ${USER} are fine"
fi
fi
done << EOF
${USERDATA}
EOF
if [ ${FOUND} -eq 1 ]; then
Display --indent 2 --text "- Permissions of home directories" --result "${STATUS_WARNING}" --color RED
ReportSuggestion "${TEST_NO}" "Double check the permissions of home directories as some might be not strict enough."
else
Display --indent 2 --text "- Permissions of home directories" --result "${STATUS_OK}" --color GREEN
LogText "Result: OK, all permissions of the home directories are 750 or more restrictive"
fi
fi
#
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#
# Test : HOME-9306
# Description : Check if users own their home directories
Register --test-no HOME-9306 --weight L --network NO --category security --description "Check if users own their home directories"
if [ ${SKIPTEST} -eq 0 ]; then
# Check if users own their home directories
FOUND=0
USERDATA=$(${GREPBINARY} -E -v '^(daemon|git|halt|root|shutdown|sync)' ${ROOTDIR}etc/passwd | ${AWKBINARY} -F: '($7 !~ "/(false|nologin)$") { print }')
while read -r LINE; do
USER=$(echo ${LINE} | ${CUTBINARY} -d: -f1)
DIR=$(echo ${LINE} | ${CUTBINARY} -d: -f6)
LogText "Test: checking directory '${DIR}' for user '${USER}'"
if [ -d "${DIR}" ]; then
OWNER=$(ls -ld ${DIR} | awk -F" " '{ print $3 }')
if [ ! "${OWNER}" = "${USER}" ]; then
LogText "Result: the home directory ${DIR} of user ${USER} is owned by ${OWNER}. Correct: chown ${USER} ${DIR}"
FOUND=1
else
LogText "Result: ownership of home directory ${DIR} for user ${USER} looks to be correct"
fi
fi
done << EOF
${USERDATA}
EOF
if [ ${FOUND} -eq 1 ]; then
Display --indent 2 --text "- Ownership of home directories" --result "${STATUS_WARNING}" --color RED
ReportSuggestion "${TEST_NO}" "Double check the ownership of home directories as some might be incorrect."
else
Display --indent 2 --text "- Ownership of home directories" --result "${STATUS_OK}" --color GREEN
LogText "Result: OK, all users own their home directories"
fi
fi
#
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#
# Test : HOME-9310
# Description : Check for suspicious shell history files
Register --test-no HOME-9310 --weight L --network NO --category security --description "Checking for suspicious shell history files"
if [ ${SKIPTEST} -eq 0 ]; then
if [ -n "${HOMEDIRS}" ]; then
if [ "${OS}" = "Solaris" ]; then
# Solaris doesn't support -maxdepth
FIND=$(${FINDBINARY} ${HOMEDIRS} -name ".*history" ! -type f -print)
else
FIND=$(${FINDBINARY} ${HOMEDIRS} -maxdepth 1 -name ".*history" ! -type f -print)
fi
if [ -z "${FIND}" ]; then
Display --indent 2 --text "- Checking shell history files" --result "${STATUS_OK}" --color GREEN
LogText "Result: Ok, history files are type 'file'."
else
Display --indent 2 --text "- Checking shell history files" --result "${STATUS_WARNING}" --color RED
LogText "Result: the following files seem to be of the wrong file type:"
LogText "Output: ${FIND}"
LogText "Info: above files could be redirected files to avoid logging and should be investigated"
ReportWarning "${TEST_NO}" "Incorrect file type found for shell history file"
fi
LogText "Remark: History files are normally of the type 'file'. Symbolic links and other types are suspicious."
else
Display --indent 2 --text "- Checking shell history files" --result "${STATUS_SKIPPED}" --color WHITE
LogText "Result: Homedirs is empty, therefore test will be skipped"
fi
fi
#
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#
# Test : HOME-9314
# Description : Check if non local paths are found in PATH, which can be a risk, but also bad for performance
# (like searching on a filer, instead of local disk)
#Register --test-no HOME-9314 --weight L --network NO --category security --description "Create list with home directories"
#
#################################################################################
#
# Test : HOME-9350
# Description : Scan home directories for specific files, used in different tests later
# Notes : For performance reasons we combine the scanning of different files, so inode caching is used
# as much as possible for every find command
# Profile opt : ignore-home-dir (multiple lines allowed), ignores home directory
if [ -n "${REPORTFILE}" ]; then PREQS_MET="YES"; else PREQS_MET="NO"; fi
Register --test-no HOME-9350 --preqs-met ${PREQS_MET} --weight L --network NO --category security --description "Collecting information from home directories"
if [ ${SKIPTEST} -eq 0 ]; then
IGNORE_HOME_DIRS=$(${GREPBINARY} "^ignore-home-dir=" ${REPORTFILE} | ${AWKBINARY} -F= '{ print $2 }')
if [ -z "${IGNORE_HOME_DIRS}" ]; then
LogText "Result: IGNORE_HOME_DIRS empty, no paths excluded"
else
LogText "Output: ${IGNORE_HOME_DIRS}"
fi
fi
#
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#
WaitForKeyPress
#
#================================================================================
# Lynis - Security Auditing and System Hardening for Linux and UNIX - https://cisofy.com
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