Avoid These Common SSH Configuration Mistakes: Protect Your Network Today

The reason most network administrators face security breaches is because they overlook the importance of properly configuring SSH access. This happens because many administrators fail to recognize the vulnerabilities in their SSH configurations, leading to unauthorized access and potential network compromises.

In this post, we're going to walk you through the common SSH configuration mistakes to avoid, helping you protect your network and ensure secure access. Specifically, we'll cover the following main points:

• Weak Passwords
• Default SSH Port
• Disabling Root Login
• Neglecting Two-Factor Authentication (2FA)

By addressing these mistakes, you'll enhance the security of your SSH access, safeguarding your network against potential threats and unauthorized access attempts. Let's dive in and explore each point in detail, understanding their importance and how to rectify them.

Weak Passwords

Using weak passwords for SSH access compromises the security of your network. Weak passwords are easy targets for hackers attempting to gain unauthorized access. According to a Verizon Data Breach Investigations Report, 81% of hacking-related breaches are due to weak or stolen passwords.

Using strong passwords enhances network security by making it harder for attackers to crack them. The mistake to avoid is using easily guessable passwords or reusing passwords across multiple accounts. Instead, create unique, complex passwords using a combination of upper and lowercase letters, numbers, and special characters. Consider using a password manager to securely store and manage passwords.

For example, instead of using "password123" as your SSH password, create a stronger one like "P@$$w0rd!SSH". The takeaway is that strengthening passwords is an essential step in protecting your network against unauthorized access.

Default SSH Port

Leaving SSH on the default port puts your network at risk of automated attacks. Attackers use automated tools that scan common ports, including the default SSH port, to find vulnerable systems. A study by the Sans Institute found that changing the default SSH port reduced the number of automated login attempts by 97%.

Changing the default SSH port adds an extra layer of obscurity, making it harder for attackers to find and target your SSH service. The mistake to avoid is failing to change the default SSH port (typically port 22) to a non-standard port. To rectify this, modify your SSH server configuration to use a non-standard port (e.g., 2222) to deter automated attacks.

By changing the SSH port to 2222 instead of using the default port 22, you minimize the risk of automated attacks. The takeaway is that modifying the default SSH port reduces the visibility of your SSH service, enhancing your network's security.

Disabling Root Login

Enabling root login over SSH exposes your network to unnecessary risks. Allowing root login via SSH presents an attractive target for attackers, who can gain complete control over your system. A report by the UK National Cyber Security Centre (NCSC) found that 86% of reported incidents involved attempts to exploit remote administration services like SSH.

Disabling root login enhances security by preventing direct access to the root account, limiting potential damage if a compromise occurs. The mistake to avoid is allowing remote SSH access for the root user. To address this, edit the SSH server configuration to disable root login by setting "PermitRootLogin no".

By disabling root login and creating a separate user account for SSH access, such as "sshuser", you add an extra layer of security to your network. The takeaway is that preventing direct root login through SSH helps mitigate the risk of unauthorized access and potential system compromise.

Neglecting Two-Factor Authentication (2FA)

Without two-factor authentication, your SSH access is vulnerable to password-based attacks. 2FA adds an extra layer of security by requiring both something you know (password) and something you have (authentication device). Research by Google shows that enabling 2FA can prevent up to 100% of automated bot attacks.

Implementing 2FA reduces the risk of successful brute-force attacks even if passwords are compromised. The mistake to avoid is not enabling or considering the use of 2FA for SSH access. To rectify this, enforce 2FA for SSH logins by leveraging methods like time-based one-time passwords (TOTP) or hardware tokens.

For example, setting up TOTP-based 2FA using a mobile authentication app like Google Authenticator adds an additional layer of security to your SSH access. The takeaway is that enabling 2FA strengthens the security of SSH access, providing an additional layer of protection against unauthorized login attempts.

By addressing the common SSH configuration mistakes outlined above, you can significantly enhance the security of your network and protect it from potential threats. Strengthening passwords, changing the default SSH port, disabling root login, and implementing 2FA are crucial steps to fortify your SSH access.

Remember, securing your SSH configuration is an ongoing process. Regularly updating and assessing your SSH settings ensures that you stay ahead of evolving security risks. By proactively protecting your network, you safeguard your valuable data and maintain the integrity of your systems.