10 Jump Server Best Practices

A jump server, also known as a jump host or jump box, is a system on a network that is used to access and manage other systems on the network. Jump servers are typically used by system administrators and security professionals to access systems that are behind a firewall or in a different network segment.

In this article, we will discuss 10 best practices for using jump servers. By following these best practices, you can ensure that your jump server is secure and efficient.

1. Use a jump server to access the target system

When you use a jump server to access the target system, you’re essentially creating a two-hop connection. The first hop is from your machine to the jump server, and the second hop is from the jump server to the target system.

This two-hop connection has several advantages. First, it’s more secure than a direct connection because the target system is never exposed to your machine. Second, it’s more efficient because you only need to authenticate once (to the jump server) instead of twice (to the jump server and then to the target system).

Finally, using a jump server gives you the ability to audit all activity that occurs on the target system. This is because all activity is logged on the jump server, so you can review the logs to see what happened.

2. Use two-factor authentication for all users

If a hacker were to gain access to a user’s credentials, they would then have full access to the jump server. From there, they could easily pivot to other systems on the network. By requiring two-factor authentication, you can be sure that even if a hacker does get ahold of a user’s credentials, they won’t be able to login without also having possession of the user’s second factor.

There are many different types of two-factor authentication that can be used, but one of the most popular is using a time-based one-time password (TOTP) app like Google Authenticator. With this type of setup, the user will have to enter both their username and password, as well as a code that is generated by the TOTP app. Since the code is only valid for a short period of time, even if a hacker did manage to get ahold of it, it would be expired by the time they tried to use it.

3. Restrict root or administrator privileges on the jump server

If an attacker were to compromise a user account with limited privileges on the jump server, they would be unable to gain full control of the server since they would not have root or administrator privileges. This would limit the damage that could be done and make it more difficult for the attacker to move laterally within the network.

It’s also important to note that you should never log in to the jump server using a root or administrator account. Doing so would defeat the purpose of having a jump server in the first place.

4. Disable SSH password authentication and use key-based authentication

If an attacker were to gain access to your jump server, they would then have access to all of the systems that your jump server has access to. By disabling SSH password authentication and using key-based authentication, you make it much more difficult for an attacker to gain access to your jump server in the first place.

To disable SSH password authentication, edit the /etc/ssh/sshd_config file and change the following line:

PasswordAuthentication yes

to

PasswordAuthentication no

Then, restart the SSH service:

sudo service ssh restart

5. Ensure that only authorized users have access to the jump server

If unauthorized users gain access to the jump server, they would then have access to all of the systems and data that can be reached from the jump server. This could lead to a data breach or other serious security issues.

To prevent this, it’s important to set up proper authentication and authorization controls for the jump server. For example, you could use two-factor authentication or require users to connect to the jump server using a VPN.

It’s also a good idea to monitor activity on the jump server so that you can quickly detect and investigate any suspicious activity.

6. Limit user accounts with administrative privileges

If a malicious user were to gain access to a jump server with an administrative account, they would have complete control over the system. They could add new accounts, change passwords, install malware, and more.

To limit the damage that could be done in this scenario, it’s important to only give administrative privileges to the users who absolutely need them. For most users, a standard account will suffice.

It’s also a good idea to set up two-factor authentication for all user accounts on the jump server. This way, even if a malicious user were to gain access to a user’s credentials, they would still need a second factor (such as a code from a hardware token) to log in.

Finally, make sure to keep the jump server software up to date with the latest security patches. By following these best practices, you can help ensure that your jump server is secure.

7. Configure logging of all activity on the jump server

A jump server is a single point of entry into a network, which means that it’s a prime target for attackers. If an attacker were to compromise the jump server, they would then have access to all the systems on the network that can be reached from the jump server.

That’s why it’s so important to configure logging of all activity on the jump server. By logging all activity, you can see what an attacker did after they compromised the server, and you can use that information to help secure the rest of the network.

There are many different ways to configure logging, but one of the most important things to do is to send the logs to a central location where they can be monitored. This way, if an attacker does compromise the jump server, you’ll have a record of their activity that can be used to help secure the rest of the network.

8. Monitor login attempts, failed logins, and changes made by privileged users

If someone were to gain unauthorized access to your jump server, they would essentially have free reign over your entire network. This is why it’s so important to monitor login attempts and failed logins. By doing so, you can quickly identify when someone has gained unauthorized access and take steps to mitigate the damage.

Similarly, changes made by privileged users should be monitored closely. If a privileged user makes an unauthorized change, it could have serious repercussions for your network. Therefore, it’s essential to have a process in place for monitoring and auditing changes made by privileged users.

Jump servers are a powerful tool, but they must be used responsibly. By following the jump server best practices outlined above, you can help ensure that your jump server is used safely and securely.

9. Implement an audit trail for privileged users

As a privileged user, you have access to sensitive information and systems. An audit trail is a record of the actions you’ve taken while logged in to the jump server. This record can be used to track what you’ve done, when you did it, and even why you did it.

The audit trail is an important tool for security and compliance. It can be used to investigate incidents, identify unauthorized access, and understand how systems are being used.

Jump servers should be configured to create an audit trail for all privileged users. The audit trail should be stored in a central location that is secure and tamper-proof.

10. Harden the operating system running on the jump server

The jump server is a critical component of your network, and as such, it needs to be as secure as possible. One way to do this is to harden the operating system running on the jump server. Hardening the operating system means making sure that all unnecessary services and applications are disabled or removed, all security patches are applied, and all passwords are strong.

By hardening the operating system, you can make the jump server much more difficult for an attacker to compromise.