CIS Ubuntu 20.04 Level 1 Server Benchmark

password requisite pam_pwhistory.so ...existing_options... remember= use_authtok

password    requisite     pam_pwquality.so try_first_pass local_users_only retry=3 authtok_type=

difok = 4
minlen = 14
dcredit = -1
ucredit = -1
lcredit = -1
ocredit = -1
maxrepeat = 3

INACTIVE=

$ sudo getent passwd | awk -F: '{ print $1}' | uniq -d

PASS_MAX_DAYS 

PASS_MIN_DAYS 

$ sudo chage -M  USER

$ sudo chage -m 1 USER

PASS_WARN_AGE 

$ sudo cut -d: -f2 /etc/shadow
$6$kcOnRq/5$NUEYPuyL.wghQwWssXRcLRFiiru7f5JPV6GaJhNC2aK5F3PZpE/BCCtwrxRc/AInKMNX3CdMw11m9STiql12f/

$ sudo usermod -s /sbin/nologin account

auth required pam_wheel.so use_uid group=

# ls -ld DIR

umask 

umask 

UMASK 

umask 

:INPUT DROP [0:0]

$ sudo service ip6tables reload

:INPUT DROP [0:0]

$ sudo sysctl -w net.ipv6.conf.all.accept_ra=0

net.ipv6.conf.all.accept_ra = 0

$ sudo sysctl -w net.ipv6.conf.all.accept_redirects=0

net.ipv6.conf.all.accept_redirects = 0

$ sudo sysctl -w net.ipv6.conf.all.accept_source_route=0

net.ipv6.conf.all.accept_source_route = 0

$ sudo sysctl -w net.ipv6.conf.all.forwarding=0

net.ipv6.conf.all.forwarding = 0

$ sudo sysctl -w net.ipv6.conf.default.accept_ra=0

net.ipv6.conf.default.accept_ra = 0

$ sudo sysctl -w net.ipv6.conf.default.accept_redirects=0

net.ipv6.conf.default.accept_redirects = 0

$ sudo sysctl -w net.ipv6.conf.default.accept_source_route=0

net.ipv6.conf.default.accept_source_route = 0

$ sudo sysctl -w net.ipv4.conf.all.accept_redirects=0

net.ipv4.conf.all.accept_redirects = 0

$ sudo sysctl -w net.ipv4.conf.all.accept_source_route=0

net.ipv4.conf.all.accept_source_route = 0

$ sudo sysctl -w net.ipv4.conf.all.log_martians=1

net.ipv4.conf.all.log_martians = 1

$ sudo sysctl -w net.ipv4.conf.all.rp_filter=1

net.ipv4.conf.all.rp_filter = 1

$ sudo sysctl -w net.ipv4.conf.all.secure_redirects=0

net.ipv4.conf.all.secure_redirects = 0

$ sudo sysctl -w net.ipv4.conf.default.accept_redirects=0

net.ipv4.conf.default.accept_redirects = 0

$ sudo sysctl -w net.ipv4.conf.default.accept_source_route=0

net.ipv4.conf.default.accept_source_route = 0

$ sudo sysctl -w net.ipv4.conf.default.log_martians=1

net.ipv4.conf.default.log_martians = 1

$ sudo sysctl -w net.ipv4.conf.default.rp_filter=1

net.ipv4.conf.default.rp_filter = 1

$ sudo sysctl -w net.ipv4.conf.default.secure_redirects=0

net.ipv4.conf.default.secure_redirects = 0

$ sudo sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=1

net.ipv4.icmp_echo_ignore_broadcasts = 1

$ sudo sysctl -w net.ipv4.icmp_ignore_bogus_error_responses=1

net.ipv4.icmp_ignore_bogus_error_responses = 1

$ sudo sysctl -w net.ipv4.tcp_syncookies=1

net.ipv4.tcp_syncookies = 1

$ sudo sysctl -w net.ipv4.conf.all.send_redirects=0

net.ipv4.conf.all.send_redirects = 0

$ sudo sysctl -w net.ipv4.conf.default.send_redirects=0

net.ipv4.conf.default.send_redirects = 0

$ sudo sysctl -w net.ipv4.ip_forward=0

net.ipv4.ip_forward = 0

$ sudo nmcli radio all off

$ sudo chgrp root /etc/group-

$ sudo chgrp shadow /etc/gshadow-

$ sudo chgrp root /etc/passwd-

$ sudo chgrp shadow /etc/shadow-

$ sudo chgrp root /etc/group

$ sudo chgrp shadow /etc/gshadow

$ sudo chgrp root /etc/passwd

$ sudo chgrp shadow /etc/shadow

$ sudo chown root /etc/group- 

$ sudo chown root /etc/gshadow- 

$ sudo chown root /etc/passwd- 

$ sudo chown root /etc/shadow- 

$ sudo chown root /etc/group 

$ sudo chown root /etc/gshadow 

$ sudo chown root /etc/passwd 

$ sudo chown root /etc/shadow 

$ sudo chmod 0644 /etc/group-

$ sudo chmod 0640 /etc/gshadow-

$ sudo chmod 0644 /etc/passwd-

$ sudo chmod 0640 /etc/shadow-

$ sudo chmod 0644 /etc/group

$ sudo chmod 0640 /etc/gshadow

$ sudo chmod 0644 /etc/passwd

$ sudo chmod 0640 /etc/shadow

*     hard   core    0

$ sudo sysctl -w fs.suid_dumpable=0

fs.suid_dumpable = 0

$ sudo sysctl -w kernel.randomize_va_space=2

kernel.randomize_va_space = 2

$ apt-get remove rpcbind