Network Penetration Testing Tutorial
Introduction
Network Penetration Testing is a method of evaluating the security of a computer network by simulating an attack from malicious outsiders (who do not have authorized access to the organization's systems) and insiders (who have some level of authorized access).
Prerequisites
Before starting with Network Penetration Testing, ensure you have the following:
- Basic understanding of networking concepts
- Knowledge of common networking protocols
- Familiarity with Linux and command line tools
- Ethical hacking mindset and respect for legal boundaries
Phase 1: Reconnaissance
In this phase, the goal is to gather as much information as possible about the target network.
1. Passive Reconnaissance
This involves gathering information without directly interacting with the target. Tools like WHOIS, Shodan, and Google Dorking can be used.
Example of Google Dorking:
site:targetdomain.com "admin login"
2. Active Reconnaissance
This involves directly interacting with the target network to gather information. Tools like Nmap and Netcat are commonly used.
Example of Nmap scan:
nmap -sS -p 1-65535 targetdomain.com
# Output will list open ports and services running on those ports
Phase 2: Scanning
In this phase, the gathered information is used to interact with the target network more extensively.
1. Network Scanning
Identify live hosts, open ports, and services running on those ports. Nmap is a powerful tool for this purpose.
Example of Nmap service version detection:
nmap -sV targetdomain.com
# Output will include the version of services running on open ports
2. Vulnerability Scanning
Identify known vulnerabilities in the services running on the target network. Tools like Nessus and OpenVAS are useful for this.
Example of Nessus scan:
# Configure and run a Nessus scan on targetdomain.com
Phase 3: Gaining Access
In this phase, the goal is to exploit vulnerabilities to gain unauthorized access to the target network.
1. Exploitation
Use tools like Metasploit to exploit identified vulnerabilities.
Example of Metasploit exploitation:
use exploit/windows/smb/ms17_010_eternalblue
set RHOST target_ip
exploit
# Output will show successful exploitation and shell access
Phase 4: Maintaining Access
After gaining access, the next step is to maintain that access for as long as needed.
1. Creating Backdoors
Install backdoors or other persistent methods to ensure re-entry.
Example of creating a persistent backdoor using Metasploit:
use exploit/windows/local/persistence
set SESSION session_id
exploit
# Output will show successful creation of a persistent backdoor
Phase 5: Covering Tracks
Covering tracks is essential to avoid detection and ensure the integrity of the compromised system is maintained.
1. Clearing Logs
Delete or alter logs to remove evidence of the attack.
Example of clearing logs on a Linux system:
echo "" > /var/log/auth.log
echo "" > /var/log/syslog
Conclusion
Network Penetration Testing is a crucial aspect of cybersecurity. It helps in identifying and mitigating security vulnerabilities before malicious actors can exploit them. Always remember to perform penetration testing ethically and within the confines of the law.