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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.
#
#################################################################################
#
# Shells
#
#################################################################################
#
IDLE_TIMEOUT=0
InsertSection "${SECTION_SHELLS}"
#
#################################################################################
#
# bash
# Files (interactive login shells): /etc/profile $HOME/.bash_profile
# $HOME/.bash_login $HOME/.profile
# Files (interactive non-login shells): $HOME/.bash_rc
#
# csh/tcsh
# Files: /etc/csh.cshrc /etc/csh.login
#
# zsh
# Files: /etc/zshenv /etc/zsh/zshenv $HOME/.zshenv /etc/zprofile
# /etc/zsh/zprofile $HOME/.zprofile /etc/zshrc /etc/zsh/zshrc
# $ZDOTDIR/.zshrc /etc/zlogin /etc/zsh/zlogin
SHELL_LOGIN_FILES="${ROOTDIR}etc/csh.cshrc ${ROOTDIR}etc/csh.login ${ROOTDIR}etc/zshenv ${ROOTDIR}etc/zsh/zshenv
${ROOTDIR}etc/zprofile ${ROOTDIR}etc/zsh/zprofile ${ROOTDIR}etc/zshrc ${ROOTDIR}etc/zsh/zshrc
${ROOTDIR}etc/zlogin ${ROOTDIR}etc/zsh/zlogin"
#
#################################################################################
#
# Test : SHLL-6202
# Description : check all console TTYs in which root user can enter single user mode without password
Register --test-no SHLL-6202 --os FreeBSD --weight L --network NO --category security --description "Check console TTYs"
if [ ${SKIPTEST} -eq 0 ]; then
LogText "Test: Checking console TTYs"
FIND=$(${EGREPBINARY} '^console' ${ROOTDIR}etc/ttys | ${GREPBINARY} -v 'insecure')
if [ -z "${FIND}" ]; then
Display --indent 2 --text "- Checking console TTYs" --result "${STATUS_OK}" --color GREEN
LogText "Result: console is secured against single user mode without password."
else
Display --indent 2 --text "- Checking console TTYs" --result "${STATUS_WARNING}" --color RED
LogText "Result: Found insecure console in ${ROOTDIR}etc/ttys. Single user mode login without password allowed!"
LogText "Output ${ROOTDIR}etc/ttys:"
LogText "${FIND}"
ReportWarning "${TEST_NO}" "Found unprotected console in ${ROOTDIR}etc/ttys"
LogText "Possible solution: Change the console line from 'secure' to 'insecure'."
fi
fi
#
#################################################################################
#
# Test : SHLL-6211
# Description : Determine available shell according /etc/shells
Register --test-no SHLL-6211 --weight L --network NO --category security --description "Available and valid shells"
if [ ${SKIPTEST} -eq 0 ]; then
LogText "Test: Searching for ${ROOTDIR}etc/shells"
if [ -f ${ROOTDIR}etc/shells ]; then
LogText "Result: Found ${ROOTDIR}etc/shells file"
LogText "Test: Reading available shells from ${ROOTDIR}etc/shells"
SSHELLS=$(${GREPBINARY} "^/" ${ROOTDIR}etc/shells)
CSSHELLS=0; CSSHELLS_ALL=0
Display --indent 2 --text "- Checking shells from ${ROOTDIR}etc/shells"
for I in ${SSHELLS}; do
CSSHELLS_ALL=$((CSSHELLS_ALL + 1))
Report "available_shell[]=${I}"
# TODO add check for symlinked shells
if [ -f ${I} ]; then
LogText "Found installed shell: ${I}"
CSSHELLS=$((CSSHELLS + 1))
else
LogText "Shell ${I} not installed. Probably a dummy or non existing shell."
fi
done
Display --indent 4 --text "Result: found ${CSSHELLS_ALL} shells (valid shells: ${CSSHELLS})."
else
LogText "Result: ${ROOTDIR}etc/shells not found, skipping test"
fi
fi
#
#################################################################################
#
# Test : SHLL-6220
# Description : Check for idle session killing tools or settings
Register --test-no SHLL-6220 --weight L --network NO --category security --description "Idle session killing tools or settings"
if [ ${SKIPTEST} -eq 0 ]; then
IDLE_TIMEOUT_METHOD=""
IDLE_TIMEOUT_READONLY=""
LogText "Test: Search for session timeout tools or settings in shell"
if IsRunning "timeoutd"; then
IDLE_TIMEOUT=1
LogText "Result: found timeoutd process to kill idle sessions"
IDLE_TIMEOUT_METHOD="timeout-daemon"
fi
if IsRunning "autolog"; then
IDLE_TIMEOUT=1
LogText "Result: found autolog process to kill idle sessions"
Report "session_timeout_method[]=autolog"
IDLE_TIMEOUT_METHOD="autolog"
fi
if [ -f ${ROOTDIR}etc/profile ]; then
# Determine if we can find a TMOUT value
FIND=$(${GREPBINARY} 'TMOUT=' ${ROOTDIR}etc/profile | ${TRBINARY} -d ' ' | ${TRBINARY} -d '\t' | ${GREPBINARY} -v "^#" | ${SEDBINARY} 's/export//' | ${SEDBINARY} 's/#.*//' | ${AWKBINARY} -F= '{ print $2 }')
# Determine if the value is exported (with export, readonly, or typeset)
FIND2=$(${GREPBINARY} '\(export\|readonly\|typeset -r\)[ \t]*TMOUT' ${ROOTDIR}etc/profile | ${GREPBINARY} -v "^#" | ${SEDBINARY} 's/#.*//' | ${AWKBINARY} '{ print $1 }')
if [ -n "${FIND}" ]; then
N=0; IDLE_TIMEOUT=1
for I in ${FIND}; do
LogText "Output: ${I}"
Report "session_timeout_value[]=${I}"
N=$((N + 1))
done
if [ ${N} -eq 1 ]; then
LogText "Result: found TMOUT value configured in ${ROOTDIR}etc/profile"
else
LogText "Result: found several TMOUT values configured in ${ROOTDIR}etc/profile"
fi
IDLE_TIMEOUT_METHOD="profile"
else
LogText "Result: could not find TMOUT setting in ${ROOTDIR}etc/profile"
fi
if [ -n "${FIND2}" ]; then
N=0;
for I in ${FIND2}; do
LogText "Output: ${I}"
if [ "${I}" = "readonly" -o "${I}" = "typeset" ]; then
N=$((N + 1))
fi
done
if [ ${N} -gt 0 ]; then
LogText "Result: found readonly setting in ${ROOTDIR}etc/profile (readonly or typeset -r)"
IDLE_TIMEOUT_READONLY=1
else
LogText "Result: NO readonly setting found in ${ROOTDIR}etc/profile (readonly or typeset -r)"
IDLE_TIMEOUT_READONLY=0
fi
else
LogText "Result: could not find export, readonly or typeset -r in ${ROOTDIR}etc/profile"
fi
else
LogText "Result: skip ${ROOTDIR}etc/profile test, file not available on this system"
fi
if [ -d ${ROOTDIR}etc/profile.d ]; then
FIND=$(${LSBINARY} ${ROOTDIR}etc/profile.d/*.sh 2> /dev/null)
if [ -n "${FIND}" ]; then
# Determine if we can find a TMOUT value
FIND=$(${FINDBINARY} -L ${ROOTDIR}etc/profile.d -name "*.sh" -type f -exec cat {} \; 2> /dev/null | ${GREPBINARY} 'TMOUT=' | ${TRBINARY} -d ' ' | ${TRBINARY} -d '\t' | ${GREPBINARY} -v "^#" | ${SEDBINARY} 's/export//' | ${SEDBINARY} 's/#.*//' | ${AWKBINARY} -F= '{ print $2 }')
# Determine if the value is exported (with export, readonly, or typeset)
FIND2=$(${FINDBINARY} -L ${ROOTDIR}etc/profile.d -name "*.sh" -type f -exec cat {} \; 2> /dev/null | ${GREPBINARY} '\(export\|readonly\|typeset -r\)[ \t]*TMOUT' | ${GREPBINARY} -v "^#" | ${SEDBINARY} 's/#.*//' | ${AWKBINARY} '{ print $1 }')
if [ -n "${FIND}" ]; then
N=0; IDLE_TIMEOUT=1
for I in ${FIND}; do
LogText "Output: ${I}"
Report "session_timeout_value[]=${I}"
N=$((N + 1))
done
if [ ${N} -eq 1 ]; then
LogText "Result: found TMOUT value configured in one of the files in ${ROOTDIR}etc/profile.d directory"
else
LogText "Result: found several TMOUT values configured in one of the files in ${ROOTDIR}etc/profile.d directory"
fi
IDLE_TIMEOUT_METHOD="profile.d"
else
LogText "Result: could not find TMOUT setting in ${ROOTDIR}etc/profile.d/*.sh"
fi
# Check for readonly
if [ -n "${FIND2}" ]; then
N=0;
for I in ${FIND2}; do
LogText "Output: ${I}"
if [ "${I}" = "readonly" -o "${I}" = "typeset" ]; then
N=$((N + 1))
fi
done
if [ ${N} -gt 0 ]; then
LogText "Result: found readonly setting in ${ROOTDIR}etc/profile (readonly or typeset -r)"
IDLE_TIMEOUT_READONLY=1
else
LogText "Result: NO readonly setting found in ${ROOTDIR}etc/profile (readonly or typeset -r)"
IDLE_TIMEOUT_READONLY=0
fi
else
LogText "Result: could not find export, readonly or typeset -r in ${ROOTDIR}etc/profile"
fi
fi
else
LogText "Result: skip ${ROOTDIR}etc/profile.d directory test, directory not available on this system"
fi
if [ -n "${IDLE_TIMEOUT_METHOD}" ]; then
Report "session_timeout_method[]=${IDLE_TIMEOUT_METHOD}"
fi
if [ -n "${IDLE_TIMEOUT_READONLY}" ]; then
Report "session_timeout_set_readonly=${IDLE_TIMEOUT_READONLY}"
fi
if [ ${IDLE_TIMEOUT} -eq 1 ]; then
Display --indent 4 --text "- Session timeout settings/tools" --result "${STATUS_FOUND}" --color GREEN
AddHP 3 3
else
Display --indent 4 --text "- Session timeout settings/tools" --result "${STATUS_NONE}" --color YELLOW
AddHP 1 3
fi
fi
#
#################################################################################
#
# Test : SHLL-6230
# Description : Check for umask values in shell configurations
SHELL_CONFIG_FILES="${ROOTDIR}etc/bashrc ${ROOTDIR}etc/bash.bashrc ${ROOTDIR}etc/bash.bashrc.local ${ROOTDIR}etc/csh.cshrc ${ROOTDIR}etc/profile"
Register --test-no SHLL-6230 --weight H --network NO --category security --description "Perform umask check for shell configurations"
if [ ${SKIPTEST} -eq 0 ]; then
FOUND=0
Display --indent 2 --text "- Checking default umask values"
for FILE in ${SHELL_CONFIG_FILES}; do
HARDENING_POSSIBLE=0
FIND=""
if [ -f ${FILE} ]; then
LogText "Result: file ${FILE} exists"
FOUND=1
FIND=$(${GREPBINARY} umask ${FILE} | ${SEDBINARY} 's/^[ \t]*//g' | ${SEDBINARY} 's/#.*$//' | ${GREPBINARY} -v "^$" | ${AWKBINARY} '{ print $2 }')
if IsEmpty "${FIND}"; then
LogText "Result: did not find umask configured in ${FILE}"
Display --indent 4 --text "- Checking default umask in ${FILE}" --result "${STATUS_NONE}" --color YELLOW
else
for UMASKVALUE in ${FIND}; do
LogText "Result: found umask ${UMASKVALUE} in ${FILE}"
case ${UMASKVALUE} in
027|0027|077|0077)
LogText "Result: umask ${UMASKVALUE} is considered a properly hardened value"
;;
*)
LogText "Result: umask ${UMASKVALUE} can be hardened "
HARDENING_POSSIBLE=1
;;
esac
done
if [ ${HARDENING_POSSIBLE} -eq 0 ]; then
Display --indent 4 --text "- Checking default umask in ${FILE}" --result "${STATUS_OK}" --color GREEN
AddHP 3 3
else
Display --indent 4 --text "- Checking default umask in ${FILE}" --result "${STATUS_WEAK}" --color YELLOW
AddHP 1 3
fi
fi
else
LogText "Result: file ${FILE} not found"
fi
done
fi
#
#################################################################################
#
Report "session_timeout_enabled=${IDLE_TIMEOUT}"
WaitForKeyPress
#
#================================================================================
# Lynis - Copyright 2007-2021, CISOfy - http://cisofy.com
|
