Linux Home server hardening: Security Best practices and tips

What is a Home linux server & why are they becoming popular?

A home Linux server is a computer or small form factor device that runs the Linux operating system and is used for a variety of tasks such as file sharing, backups, media streaming, remote access, and running personal websites or applications. Because of the following factors, these servers are becoming more popular among tech enthusiasts, developers, and small businesses:

• Cost-effective: Because Linux servers can be built with off-the-shelf hardware, they are a less expensive option than proprietary solutions.
• Flexibility: Linux servers provide a wide range of software options and can be tailored to specific requirements.
• Reliability: Linux servers are well-known for their stability and dependability, making them an excellent choice for mission-critical applications.
• Security: Linux servers can be configured to be more secure than other operating systems, making them suitable for use in a home environment.
• Learning opportunities: Setting up and configuring a home Linux server can be a great learning opportunity for those interested in system administration, networking, and security.

• The ability to access it from anywhere: With the help of remote access tools, you can access your home Linux server from anywhere, this way you can access your files, backups, and other content remotely.

Overall, home Linux servers are a great option for those looking to take control of their IT infrastructure, whether for personal or business use, and can provide a cost-effective, reliable, and secure solution for various tasks.

Why do we need to "harden" a home server?

Hardening a home Linux server is an essential step in protecting it from various types of cyberattacks and ensuring that it remains stable and secure. The process of hardening a Linux server involves implementing various security measures to reduce its attack surface and improve its overall security. Here are a few reasons why hardening a home Linux server is important:

• Protection from cyberattacks: Hardening a home Linux server can help protect it from various types of cyberattacks such as malware, phishing, and intrusion attempts.
• Compliance with regulations: Some businesses are required to comply with regulatory standards such as HIPAA, PCI-DSS, and SOC2. Hardening a Linux server can help ensure compliance with these regulations and avoid penalties for non-compliance.
• Data protection: A home Linux server is often used for storing and sharing personal and business data. Hardening the server can help protect this data from unauthorized access, theft, and loss.
• Protecting other devices on the network: A home Linux server is often connected to other devices on the network such as PCs, laptops, and smartphones. Hardening the server can help protect these devices from various types of cyber threats.
• Maintaining the availability of the services: Hardening a Linux server can help ensure that the services provided by the server remain available and operational at all times. This can be especially important for businesses that rely on their servers to operate and provide services to their customers.

Overall, hardening a home Linux server is an essential step in protecting it from various types of cyberattacks and ensuring that it remains stable and secure. It is essential for the protection of personal and business data, compliance with regulations, and maintaining the availability of the services provided by the server.

Understanding the threats

Home Linux servers are vulnerable to a variety of cyberattacks, here are some of the most common types of attacks:

• Brute force attacks: Brute force attacks are a type of cyberattack where an attacker repeatedly tries different combinations of username and password in an attempt to gain unauthorized access to the server.
• SQL injection attacks: SQL injection attacks are a type of cyberattack where an attacker injects malicious code into a SQL query in an attempt to gain unauthorized access to the server.
• Remote code execution (RCE) attacks: Remote code execution attacks are a type of cyberattack where an attacker exploits a vulnerability in the server software to execute arbitrary code on the server.
• Distributed Denial of Service (DDoS) attacks: DDoS attacks are a type of cyberattack where an attacker floods a server with traffic in an attempt to overload it and make it unavailable to legitimate users.
• Phishing attacks: Phishing attacks are a type of cyberattack where an attacker sends an email or message, disguising as a trustworthy entity, in an attempt to trick the user into providing sensitive information such as login credentials.
• Malware attacks: Malware attacks are a type of cyberattack where an attacker uses malware to compromise the server and gain unauthorized access to sensitive data or disrupt its operation.
• Zero-day attacks: Zero-day attacks are a type of cyberattack that exploit previously unknown vulnerabilities

What happens when a Home server is attacked?

A successful attack on a home Linux server can have a range of negative impacts, some of which can include:

• Data Loss: A successful attack on a home Linux server can result in the loss of important personal or business data. This can include sensitive information such as financial data, personal identification numbers, and confidential business information.
• Loss of service: A successful attack on a home Linux server can result in the loss of service, making it unavailable to legitimate users. This can be especially devastating for businesses that rely on their servers to operate and provide services to their customers.
• Reputation Damage: A successful attack on a home Linux server can result in damage to the reputation of the server's owner. This can include negative media coverage, loss of trust from customers(in case of a home based venture), and a general negative perception of the server's owner.
• Financial Loss: A successful attack on a home Linux server can result in financial loss. This can include the cost of recovering from the attack, such as paying for professional services to restore data and repair damage, as well as lost revenue due to the loss of service.
• Legal Liability: A successful attack on a home Linux server can result in legal liability. This can include penalties for non-compliance with regulatory standards and civil suits brought by individuals or organizations that have suffered damages as a result of the attack.
• Further attacks: A successful attack on a home Linux server can be used as a stepping stone for the attacker to launch further attacks on the network or other devices connected to the server.

Overall, a successful attack on a home Linux server can have severe and far-reaching consequences. It is important for the server's owner to take the necessary steps to harden the server and protect it from cyberattacks.

Updates are your best friend

Keeping a home Linux server and its software updated is an important aspect of maintaining the security and stability of the server. Here are a few reasons why keeping the server and its software updated is important:

• Security: Software updates often include security patches that address known vulnerabilities in the software. Failing to update the software can leave a server exposed to these vulnerabilities and vulnerable to cyberattacks.
• Stability: Software updates often include bug fixes and performance improvements that can help ensure the stability of the server.
• Compliance: Some software may be required to be updated in order to comply with regulatory standards such as HIPAA, PCI-DSS, and SOC2.
• New features: Software updates often include new features and improvements that can enhance the functionality and usability of the server.
• Vendor Support: Vendor support for software may be limited for older versions of the software. By keeping the software updated, you can ensure that you have access to the latest support and resources from the vendor.
• Compatibility: Keeping the software updated can ensure compatibility with other devices and software on the network.

In short, keeping a home Linux server and its software updated is an important aspect of maintaining the security and stability of the server. It can help protect the server from vulnerabilities, ensure compliance with regulatory standards, and ensure compatibility with other devices and software on the network.

Some best Practices for Hardening a Home Linux Server

Secure Remote Access

Remote access to a home Linux server allows users to access the server's resources and services from a remote location. However, if remote access is not properly secured, it can leave the server vulnerable to cyberattacks. Ensuring secure remote access helps to protect the server from unauthorized access and intrusion attempts.

Tips for setting up secure remote access:

1. Use secure protocols such as SSH or VPN for remote access
2. Use strong and unique passwords for remote access
3. Limit the number of users who have remote access to the server
4. Use two-factor authentication for remote access
5. Regularly review and revoke access for inactive or unnecessary users

Firewall Configuration

A firewall is a network security system that monitors and controls incoming and outgoing network traffic. It can help protect a home Linux server from various types of cyberattacks such as malware, phishing, and intrusion attempts.

Tips for configuring a firewall:

1. Enable the built-in firewall on the Linux server
2. Configure the firewall to only allow necessary incoming and outgoing traffic
3. Regularly review and update the firewall rules
4. Use an intrusion detection system (IDS) to detect and alert on potential threats

User and Permission management

User and permission management controls who can access the server and what actions they can perform on the server. Properly managing users and permissions can help protect the server from unauthorized access and intrusion attempts.

Tips for managing users and permissions:

1. Use strong and unique passwords for all users
2. Limit the number of users who have access to the server
3. Regularly review and revoke access for inactive or unnecessary users
4. Use role-based access control (RBAC) to assign permissions based on job function

File permissions

File permissions control who can access and make changes to files on the server. Properly managing file permissions can help protect the server from unauthorized access and intrusion attempts.

Tips for setting file permissions:

1. Use the least privilege principle to assign the least amount of permissions necessary for a user to perform their tasks
2. Regularly review and update file permissions
3. Use access control lists (ACLs) to fine-tune file access

Monitoring and Logging

Monitoring and logging refer to the process of tracking and recording activity on a home Linux server. This includes system and network activity, user activity, and security-related events. By monitoring and logging the activity on the server, it can help identify potential security threats and troubleshoot issues.

Tips for setting up monitoring and logging:

1. Configure the server to log all activity, including system and network activity, user activity, and security-related events
2. Regularly review the logs for any suspicious activity or errors
3. Use log analysis tools to make sense of the log data
4. Use an intrusion detection system (IDS) to detect and alert on potential threats
5. Send logs to a remote server or service for safekeeping and analysis
6. Establish a logging policy that can help you to meet regulatory compliance requirements
7. Apply retention policies to log data in order to meet compliance and regulatory requirements.

Do even more, additional security for your server

Virtual Private Networks (VPNs)

A virtual private network (VPN) is a method of securely extending a private network over a public network, such as the internet. VPNs use encryption and other security measures to protect data and traffic from unauthorized access. By using a VPN, it can help secure remote access to a home Linux server and protect the server from cyberattacks.

Tips for setting up a VPN:

1. Research different VPN options and choose one that meets your needs
2. Configure the VPN on the Linux server and all devices that will be accessing the server
3. Use strong and unique authentication credentials for the VPN
4. Regularly review and update the VPN configuration
5. Monitor the VPN for any potential issues or security threats

Two-factor authentication (2FA)

Two-factor authentication (2FA) is a method of authentication that requires the user to provide two forms of identification. This can include something they know, such as a password, and something they have, such as a security token or a mobile device. 2FA helps to protect a home Linux server from unauthorized access and intrusion attempts.

Tips for setting up 2FA:

1. Research different 2FA options and choose one that meets your needs
2. Configure 2FA on the Linux server and all devices that will be accessing the server
3. Use strong and unique authentication credentials
4. Regularly review and update the 2FA configuration
5. Monitor the 2FA for any potential issues or security threats
6. Educate users on the importance and proper use of 2FA.

Conclusion

Hardening a home Linux server is an essential step in protecting it from various types of cyberattacks and ensuring that it remains stable and secure.

It is important to consider various best practices such as secure remote access, firewall configuration, user and permission management, file permissions, monitoring and logging, virtual private networks (VPNs) and Two-factor authentication (2FA) in order to ensure the security of the server. By following these best practices and staying up-to-date with the latest security measures, you can help protect your home Linux server from cyber threats and ensure that it remains stable and secure.

Remember that security is an ongoing process, it's important to review and update your security measures regularly and stay aware of new threats and vulnerabilities.