You should know the ways of preventing your Linux VPS from cyber attacks. Besides applying the best security practices, your job does not end there. You constantly need to monitor the virtual private server. Cyber attackers are always on the lookout and keep searching for an open door to break into your virtual space. For this purpose, we have brought 15 useful VPS security tips to cope with different weaknesses of Linux security and further strengthen your wall of defense.
Linux Security and Its Common Weaknesses
Let us first have a look at what we are dealing with. Although Linux is famous for its security system, nothing is perfect and has some flaws. Many security threats can damage your server’s security and the data stored on it.
It is an intrusive software specially designed by cyber attackers to harm computers and Operating Systems. It has many different forms like Trojans, ransomware, virus, and spyware.
It happens when an attacker uses packet sniffers to intercept and extract data from your network.
It is a hacking method in which the hackers try to guess your login credentials using trial and error.
It happens when an attacker tries to manipulate a code in a web application to gain access to your server’s database.
Cross-Site Scripting (XSS):
It is a client-side attack in which a hacker runs some malicious code into your website to gain access to your server and other personal files.
It can happen when a server cannot verify the access right properly and end up giving root privileges to general users.
It comes under virtual identity theft, and it happens because of unencrypted data, weak passwords, or poorly set app session time-outs.
What should you monitor?
Before employing any security measures, there are certain factors you should monitor, viz.
- VPS Security Hosting
- Server Software
- SSH Connection
- Root access and logins
- Passwords and credentials
- FTP Connection
- User’s rights and privileges
- Server logs
How Can You Strengthen Your Server’s Security
Above, we have discussed some things to monitor before employing any security measures. Now let us discuss the ways you can use to strengthen your server’s security.
Research Your Web Hosting Security:
When choosing your hosting provider, make sure to have a piece of complete knowledge about their security infrastructure and what additional protection they offer to keep your server safe; this includes firewall, etc. If going for shared hosting, you need to be extra careful and concerned about the security of your server. It is better if the hosting provider offers you an automated backup for your site to restore it in case of any mishap.
Change the Default SSH Port:
If you still use port 22 to access your virtual server through SSH Connection, there is a high chance for hackers to target you. The reason mainly is that hackers can scan open the ports by Brute-Force attacks. So seek out your hosting providers for assistance in this regard. We will not go into further details as it might be complicated for many people.
Disable Root Logins:
Every Linux VPS has a root user who enjoys the most privileges as compared to other users. Cyber attackers try to hack them to gain complete access to the system. Hence, it is a good practice to disable logins from root users to protect your server. It is also advised to create an alternative username with the same privileges to execute the root-level commands.
You can reach out to professionals for help in this regard. We will not discuss this in detail because of its technical nature.
Imply Strong Passwords:
Passwords are your first line of defense. Therefore, you need to be very careful when deciding on one for your accounts. You should use a longer password instead of a short one and try to avoid using personal information while creating them. Try to think out of the box and use a combination of upper and lower-case alphabets, numbers, and characters to make it hard for cyber attackers to guess. Most cyber-attacks are successful because of weak passwords. Moreover, try to use different passwords for different accounts and platforms.
Use SSH Keys:
Using a password to log into your SSH account makes you more susceptible to cyber-attacks because of brute-force attacks. But you can easily prevent this from happening by using SSH keys. These keys are more reliable, authentic, and secure as compared to passwords. They are generated by computers and can be 4096 bits in length which makes them longer and more complex than passwords.
SSH keys are in two sets, i.e., public and private. Public keys are saved on the server, and private ones are saved on the user’s machine. When someone tries to log in, the server generates a random string and encrypts it with a public key which can only be decrypted using an associated private key.
To generate SSH keys, it is better to seek some professional help if you do not have the technical knowledge yourself; if you do, switch to it as soon as possible. We will not go into further details as the topic lies more on the technical side.
Internal Firewall (IP Tables):
HTTP traffic can come from anywhere, so you need to have a filter that will only allow visitors with a good reputation to access your system. This will help to avoid DDoS attacks and unwanted traffic slowing down your server. Linux distributions come with internal firewalls, aka Ip tables. This tool monitors all the traffic from and to your server using rules known as a chain to filter incoming and outgoing data packets. You can adjust the setting of this tool according to your needs or seek help from a professional. We will not go into further details because of the technical nature of the procedure.
Configure your UFW Firewall:
Enabling an Uncomplicated Firewall (UFW) is another step you can take to secure your server and control your system’s inbound and outbound traffic. In reality, it is a Netfilter firewall which is very easy to use. UFW acts as a front-end for IP tables and is usually pre-installed on Linux distributions. What it does is it denies all the incoming connections and allows outgoing ones, which decreases the risk of potential threats. Moreover, you can adapt the rules according to your needs. To enable it, you can either consult a professional or do it yourself if you have the technical knowledge.
Use SFTP instead of FTP:
FTP connections are not encrypted, but when employed over TLS (FTPS), they only encrypt credentials, not the files. Therefore, using both of them puts you at high risk of getting hacked. Hackers can use the sniffing attack to steal your credentials and intercept your files and data later.
To be on the safer side, either use FTP over SSH or SFTP instead. SFTP provides complete encryption for all the data, including your credentials and files. It also prevents the user from man-in-the-middle attacks because the client needs to be approved and authenticated by the server before gaining access to your system. To enable it, you can consult an expert or can try doing it yourself if you have the brain for it. But it is a good step towards increasing the security of your server.
Set up Fail2Ban:
Fail2Ban is software that keeps an eye on the system logs and blocks hackers after multiple failed login attempts. It also protects the system from DDoS, DoS, Brute-force, and dictionary attacks. It uses iptables and a firewall to block IP addresses. You can follow some easy steps and enable it yourself or ask an expert to do so for you. Either way, you will end up with improved security for your system.
Install an Antivirus:
An antivirus is software that helps you detect viruses and clean them for you. In addition to a firewall to filter your incoming traffic, you should also have an antivirus to keep a check on the files stored on your VPS. Hackers use different kinds of viruses to infect your system, so make sure to use up-to-date antivirus and strengthen your defense line further. Antiviruses are very easy to install. You can either do it yourself or seek professional help.
Set up a VPN for your VPS:
First of all, you should avoid using an open public connection for the sake of your system’s safety because there is a high chance that someone is trying to intercept your traffic and steal your data. But if you use it, you should most certainly use a VPN to avoid these troubles. A VPN will route your traffic through an encrypted tunnel while concealing your original location, and your device will use the VPN’s IP address. This way, you can avoid using your IP address while surfing the Internet, maintaining your invisibility. If your IP address is concealed, hackers will not be able to intercept your traffic. It is an amazing tool to use with a firewall and enhances your security tenfold. Either set it up yourself or seek an expert’s help and improve your security.
Review User’s Rights:
If many people use your VPS hosting, you should be extremely careful while distributing the controls and rights among them. It is not advised to provide root-level privileges to all the users because it might put resource usage and sensitive data at risk. Hence, it is best to set an access limit for each user to prevent such problems. You can manage the users and allow them different levels of permissions to particular sets of files and resources.
Linux has system privilege features that can help in defining users’ rights. It can be done by following simple steps, which we shall not discuss here because it might get a little technical.
Internet Protocol version 6 (IPv6) is the most recent version that allows you to communicate over the Internet. It provides an identification and location system for computers within a network. But enabling it means exposing your security vulnerabilities, making your VPS hosting more susceptible to cyber-attacks. A hacker can easily send malicious traffic through an IPv6. It is not necessary for you to actively use IPv6 for it to harm you, even if some of the programs open listing sockets on it will do the damage, as it will process any packet that comes its way, be it a malicious one. So it is suggested to disable your IPv6. Follow some basic steps if you have the knowledge of it, or hire a professional to do it for you.
Monitor your Server’s Logs:
You need to monitor your server’s logs to control what happens with your VPS hosting. These logs are also helpful in analyzing and creating reports of detailed information about your server’s current state.
These server logs can actually tell you if the server has been subjected to cyber attacks or other security threats. And you can fix all the vulnerabilities before it is too late. On Linux systems, /var/log is one of the critical directories that store a collection of log files consisting of vital information about your system, kernel package managers, and different other applications running on the server. To open /var/log and monitor your logs, follow some basic steps, which we shall explain in detail.
Keep your Applications Up-to-Date:
New updates are released to fix the problems and bugs of the previous versions. The older the version of an application is, the more vulnerable it becomes. The updates can be installed in just a few clicks, be sure to stay on the latest version of your applications to avoid security threats and cyber-attacks.
The security of your VPS should be your top priority, and you should take every step possible to improve it. This article has brought to you some useful tips which you can employ to be on the safer side and avoid successful cyber-attacks and other security threats from happening. You can ensure the security of your credentials and your files within your system. We hope that this article will prove helpful to you and make your experience trouble-free.