Table of contents
1.
Introduction
2.
What Are The Various Security Requirements?
3.
Threats And Vulnerabilities
4.
Security Measures
4.1.
Permissions 
4.2.
Use A Firewall To Protect The Network
4.3.
Protecting wireless networks
4.4.
Networking protocols
4.5.
Using the Blocking Technique
4.6.
Anti-Virus
4.7.
Software Updates
4.8.
Security Testing
5.
Frequently Asked Questions 
5.1.
Mention the various requirements of security.
5.2.
Why should we run Anti-virus scans on Linux OS?
5.3.
What do you mean by SSH?
5.4.
What does a Firewall do? How does it work?
5.5.
Where are the password details kept in UNIX OS?
6.
Conclusion
Last Updated: Mar 27, 2024

Linux Security

Author Geetika Dua
0 upvote

Introduction

Linux has been in great demand due to its fancy features and ease of access. But how does it manage to provide security? To know about the security aspect of Linux, keep reading!

linux security

Linux users are less prone to viruses than other operating systems, but many security issues still need to be taken care of. 

What Are The Various Security Requirements?

We must fulfill some security requirements due to laws and regulations. Other security aspects are for the user and the safety of data.

We need to consider the following factors-

  • Authorization - Only allow limited access
  • Authenticity - Verifying the identity
  • Privacy and Integrity- Ensure personal information and data are not compromised.
  • Availability - We need to ensure that the system can perform its required function.
     

The next question may arise: why do we need to impose so much security? Who are we protecting our systems from? How do they endanger the integrity of your system?

Let us look at the answers to these questions.

Threats And Vulnerabilities

threats
  • Theft Of Data- Our computers have private information that we should protect. If this data goes into unsafe hands, it can lead to damages and losses.
  • Manipulation Of Data- If someone not supposed to access the data gets it somehow, they can modify its contents. This is a more considerable risk as the authenticity of information is lost.
  • Denial Of Service-Denial of Service (DoS) attacks are where the attacker disables or makes unusable the services provided by the system. These types of attacks happened with companies like Yahoo in the 2000s. These are complex attacks and need to be tackled.
  • Direct Access To Computer- It is a common practice that we can use your computer to cause attacks by logging into other user accounts. We can use your machine to cause damage, and this situation becomes highly disgraceful.

Security Measures

Security measures

The following security measures are the most powerful ones. Let us look at each one of them.

Permissions 

The conventional authentication method uses a username and password. The username is not-so-hidden information, as everyone can see, Although the password is encrypted. It is only known to the user. The algorithm employed for encryption is one-way and rechecked every time a user enters the password.

In UNIX, the details of the passwords are present in the/etc/passwd file. This is prone to harm. Linux OS prevents this issue by using a shadow password file with restricted permission to read.

Use A Firewall To Protect The Network

Once your system is connected to the network, it becomes more vulnerable. We need to make sure that the transmitted data is safe. Se can do this by separating the network of computers and other networks. We can achieve this with the help of a firewall. A firewall determines whether traffic is allowed to pass or not. Firewalls are protection devices that act as a borderline between trusted and unsafe networks. 

Protecting wireless networks

Using a firewall is a wise decision, but it has disadvantages. Network signals and firewalls can be messed up. We can secure the network by using WPA wireless network encryption. We can also apply tunneling on network traffic by using VPNs.

Networking protocols

We should insist on safer protocols like SSH, which transmits the data after encrypting it. The encrypted information is coded data and is not understandable without proper decryption. Outsiders can access the shared data if we continue using standard unsecured protocols like File Transfer Protocol and Telnet. This data is tampered with because it is unencrypted. We should employ more physical security to make data transmission safe and reliable.

Using the Blocking Technique

Another method to protect your local machine from the external network is to utilize specific blocking techniques. We can block clear network access and inbound links by using personal firewalls and restricting access using configuration. We can also use other software like Tcpwrappers to employ restrictions and save the data.

Anti-Virus

Although Linux is a fancy operating system that does not require explicit Anti Virus software, it can still be a carrier and affect other operating systems which are more vulnerable. It is, therefore, a healthy practice to occasionally run scans on your system to ensure no virus. Several anti-virus packages are available to do this job.

Software Updates

No software is safe from bugs. Whenever we encounter a bug at the security level, we need to find a solution for it. We can install a software update checker to achieve this in Linux distributions. This is included in Linux. The system automatically performs checks on data getting installed from unknown sources and fixes the bug wherever found. It also manually updates itself if needed.

Security Testing

After completing the system and the network operations, we should test to see if there are any more vulnerabilities to tackle. We can achieve this by using a network port scanning or dedicated security software tester. It tests the system and network for all possible vulnerabilities. This practice of software testing for access is penetration testing. There are many open-source tools available on the internet to support security testing. One example of such a feature is the open-source network scanner, Nmap. It is used to check the vulnerabilities of the network. We should remember that we can only apply these testing methods to authorized systems. It is a criminal act to run these checks on unauthorized ones.

Frequently Asked Questions 

Mention the various requirements of security.

Authorization, Authenticity, Privacy, Integrity, and Availability are security requirements.

Why should we run Anti-virus scans on Linux OS?

Although Linux is a fancy operating system that does not require explicit Anti Virus software, it can still be a carrier and affect other operating systems which are more vulnerable.

What do you mean by SSH?

SSH stands for "Secure Shell." The SSH protocol is a secure alternative to unsecured remote shell protocols.

What does a Firewall do? How does it work?

A firewall guards your network against attackers. It scans the data that tries to enter the network and imposes restrictions on anything that looks fishy.

Where are the password details kept in UNIX OS?

In UNIX, the details of the passwords are present in the/etc/passwd file.

Conclusion

In this article, we have discussed the various security requirements and the methods to achieve them. We hope you got clarity on this topic. To read more about Linux, refer to the following articles-

Refer to our guided paths on Coding Ninjas Studio to learn more about DSA, Competitive Programming, JavaScript, System Design, etc. Enroll in our courses and refer to the mock test and problems available. Take a look at the interview experiences and interview bundle for placement preparations.

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