Network Ports

Network ports are essential communication endpoints that allow different services and applications to interact over a network. However, certain ports are frequently targeted by hackers due to their common use and potential vulnerabilities. Here’s a summary of the most commonly exploited network ports by hackers:

1. Port 20/21 (FTP – File Transfer Protocol)

• Used for file transfers.
• Vulnerable to brute-force attacks, anonymous authentication, and data interception.

2. Port 22 (SSH – Secure Shell)

• Used for secure remote access to systems.
• Targeted by brute-force attacks and credential stuffing.

3. Port 23 (Telnet)

• Used for remote access but transmits data in plaintext.
• Highly vulnerable to eavesdropping and credential theft.

4. Port 25 (SMTP – Simple Mail Transfer Protocol)

• Used for sending emails.
• Exploited for spam campaigns, phishing, and email spoofing.

5. Port 53 (DNS – Domain Name System)

• Used for resolving domain names to IP addresses.
• Targeted in DNS spoofing, cache poisoning, and DDoS attacks.

6. Port 80 (HTTP – Hypertext Transfer Protocol)

• Used for unencrypted web traffic.
• Exploited for web-based attacks like SQL injection, XSS, and phishing.

7. Port 110 (POP3 – Post Office Protocol)

• Used for retrieving emails.
• Vulnerable to brute-force attacks and data interception.

8. Port 135 (RPC – Remote Procedure Call)

• Used for inter-process communication.
• Exploited in worm propagation and remote code execution.

9. Port 139/445 (SMB – Server Message Block)

• Used for file and printer sharing.
• Targeted in ransomware attacks (e.g., WannaCry) and brute-force attempts.

10. Port 1433/1434 (Microsoft SQL Server)

• Used for database communication.
• Exploited for SQL injection and unauthorized access.

11. Port 3306 (MySQL)

• Used for MySQL database communication.
• Targeted in brute-force attacks and SQL injection.

12. Port 3389 (RDP – Remote Desktop Protocol)

• Used for remote desktop access.
• Exploited in brute-force attacks and ransomware campaigns.

13. Port 5900 (VNC – Virtual Network Computing)

• Used for remote desktop control.
• Vulnerable to brute-force attacks and unauthorized access.

14. Port 8080 (HTTP Alternate)

• Often used for web proxies or alternate HTTP services.
• Exploited for web-based attacks and unauthorized access.

15. Port 27017 (MongoDB)

• Used for MongoDB database communication.
• Targeted in brute-force attacks and data exfiltration.

Common Exploitation Techniques:

• Brute-Force Attacks: Hackers attempt to guess credentials by trying multiple username/password combinations.
• Man-in-the-Middle (MITM) Attacks: Intercepting and altering communication between two parties.
• Exploiting Vulnerabilities: Leveraging unpatched software or misconfigurations.
• Phishing and Social Engineering: Tricking users into revealing sensitive information.

Mitigation Strategies:

• Regularly update and patch software.
• Use strong authentication mechanisms (e.g., multi-factor authentication).
• Monitor and restrict access to sensitive ports.
• Implement firewalls and intrusion detection/prevention systems (IDS/IPS).
• Encrypt data in transit using protocols like TLS/SSL.

By understanding these commonly targeted ports and their associated risks, organizations can better secure their networks against potential cyber threats.