运行
curl -L https://github.com/mufengcoding/shell/releases/download/1.1/security.sh | bash
注意只运行一次 ，多次运行可能会gg
github地址：https://github.com/mufengcoding/shell/blob/master/security.sh
#!/bin/sh
# desc: setup linux system security
# author:mufengs
# powered by blog.mufengs.com
# version 0.1.2 written by 2018.11.24
#account setup
#锁定以下用户
passwd -l xfs
passwd -l news
passwd -l nscd
passwd -l dbus
passwd -l vcsa
passwd -l games
passwd -l nobody
passwd -l avahi
passwd -l haldaemon
passwd -l gopher
passwd -l ftp
passwd -l mailnull
passwd -l pcap
passwd -l mail
passwd -l shutdown
passwd -l halt
passwd -l uucp
passwd -l operator
passwd -l sync
passwd -l adm
passwd -l lp
#将帐号相关文件设为只读属性
\# chattr /etc/passwd /etc/shadow
chattr +i /etc/passwd
chattr +i /etc/shadow
chattr +i /etc/group
chattr +i /etc/gshadow
#系统登陆失败3次锁定5分钟
\# add continue input failure 3 ,passwd unlock time 5 minite
sed -i 's#auth required pam\_env.so#auth required pam\_env.so \\n auth required pam\_tally.so onerr=fail deny=3 unlock\_time=300 \\n auth required /lib/security/$ISA/pam\_tally.so onerr=fail deny=3 unlock\_time=300#' /etc/pam.d/system-auth
#5分钟超时登出
\# system timeout 5 minite auto logout
echo "TMOUT=300" \>>/etc/profile
#设置历史命令为10条
\# will system save history command list to 10
sed -i "s/HISTSIZE=1000/HISTSIZE=10/" /etc/profile
#让以上配置生效
\# enable /etc/profile go!
source /etc/profile
#防范SYN Flood攻击
\# add syncookie enable /etc/sysctl.conf
echo "net.ipv4.tcp\_syncookies=1" \>> /etc/sysctl.conf
sysctl -p \# exec sysctl.conf enable
\# optimizer sshd\_config
sed -i "s/#MaxAuthTries 6/MaxAuthTries 6/" /etc/ssh/sshd\_config
sed -i "s/#UseDNS yes/UseDNS no/" /etc/ssh/sshd\_config
#限制重要命令的权限
\# limit chmod important commands
chmod 700 /bin/ping
chmod 700 /usr/bin/finger
chmod 700 /usr/bin/who
chmod 700 /usr/bin/w
chmod 700 /usr/bin/locate
chmod 700 /usr/bin/whereis
chmod 700 /sbin/ifconfig
chmod 700 /usr/bin/pico
chmod 700 /bin/vi
chmod 700 /usr/bin/which
chmod 700 /usr/bin/gcc
chmod 700 /usr/bin/make
chmod 700 /bin/rpm
\# history security
chattr +a /root/.bash\_history
chattr +i /root/.bash\_history
\# write important command md5
cat \> list << "EOF" &&
/bin/ping
/bin/finger
/usr/bin/who
/usr/bin/w
/usr/bin/locate
/usr/bin/whereis
/sbin/ifconfig
/bin/pico
/bin/vi
/usr/bin/vim
/usr/bin/which
/usr/bin/gcc
/usr/bin/make
/bin/rpm
/bin/ls
/bin/top
/bin/ps
EOF
for i in \`cat list\`
do
if \[ ! \-x $i \];then
echo "$i not found,no md5sum!"
else
md5sum $i \>> /var/log/\`hostname\`.log
fi
done
rm -f list
\# 修改默认umask
perl -npe 's/umask\\s+0\\d2/umask 077/g' -i /etc/bashrc
perl -npe 's/umask\\s+0\\d2/umask 077/g' -i /etc/csh.cshrc
#cron加固
echo "Locking down Cron"
touch /etc/cron.allow
chmod 600 /etc/cron.allow
awk -F: '{print $1}' /etc/passwd | grep -v root \> /etc/cron.deny
echo "Locking down AT"
touch /etc/at.allow
chmod 600 /etc/at.allow
awk -F: '{print $1}' /etc/passwd | grep -v root \> /etc/at.deny
#内核加固
cat << EOF >> /etc/sysctl.conf
net.ipv4.ip\_forward = 0
net.ipv4.conf.all.send\_redirects = 0
net.ipv4.conf.default.send\_redirects = 0
net.ipv4.tcp\_max\_syn\_backlog = 1280
net.ipv4.icmp\_echo\_ignore\_broadcasts = 1
net.ipv4.conf.all.accept\_source\_route = 0
net.ipv4.conf.all.accept\_redirects = 0
net.ipv4.conf.all.secure\_redirects = 0
net.ipv4.conf.all.log\_martians = 1
net.ipv4.conf.default.accept\_source\_route = 0
net.ipv4.conf.default.accept\_redirects = 0
net.ipv4.conf.default.secure\_redirects = 0
net.ipv4.icmp\_echo\_ignore\_broadcasts = 1
net.ipv4.icmp\_ignore\_bogus\_error\_responses = 1
net.ipv4.tcp\_syncookies = 1
net.ipv4.conf.all.rp\_filter = 1
net.ipv4.conf.default.rp\_filter = 1
net.ipv4.tcp\_timestamps = 0
EOF
\# 禁止所有TCP Wrappers
echo "ALL:ALL" \>> /etc/hosts.deny
echo "sshd:ALL" \>> /etc/hosts.allow
#防止缓冲区溢出
sysctl -w kernel.exec-shield=1
sysctl -q -n -w kernel.randomize\_va\_space=2
echo "kernel.exec-shield = 1"\>>/etc/sysctl.conf
echo "kernel.randomize\_va\_space = 2"\>>/etc/sysctl.conf
#禁止空密码登陆
sed -i 's/\\<nullok\\>//g' /etc/pam.d/system-auth
#定时更新
yum -y install yum-cron
chkconfig yum-cron on