Two Factor Authentication – Best for the UNIX/Linux Server Security

The UNIX/Linux server security is challenging, because these servers are at a risk of getting compromised at any point of time by the attackers. In today’s enterprise environment, the UNIX and Linux servers are growing popular. With their increased popularity, these servers have become the primary target of the attackers for security breaches. There have been numerous cases of harmful external security threats where the attackers have gained access to these servers; UNIX and Linux, through the Internet. The largest security threat to UNIX/Linux server is internal, not external. Therefore, it is must for the enterprises to improve their UNIX/Linux server security, so that comprising server becomes complicated for the hackers.

UNIX is used by 66.5 percent of all the websites whose operating system we know.

Internal security threats can come from anywhere & anytime. In UNIX/Linux servers, some of these threats that are common and extremely harmful include the following:

  • Backdoor created by a user.
  • Account duplicated by a privileged user.
  • A piece of code implanted by the system administrator or developer that may damage the server.

Security breaches – The big problem

With security breaches on the rise at an alarming rate, the UNIX/Linux server security is becoming more challenging and necessary for the system administrators. For gaining access to a server, most of the system admins worldwide rely on just a single authentication factor, i.e. the password. But, hackers or the online attackers use brute force or several other proven methods that help break password of the server and gain access to it. Therefore, it is must for the system admins to use more than just password-alone verification for optimal UNIX/Linux server security against all sorts of harmful internal or external security threats.

The solution to these threats

Adding an additional verification step in the login process is must for protecting the servers; UNIX and Linux, against security threats. One ideal & proven solution that ensures a high security level is Two Factor Authentication. The system admins must implement this solution and experience the peak security they are looking for.

An overview

Two Factor Authentication (2FA) is an authentication method that adds an additional security layer for verifying identity of a admin and completing the login procedure successfully. 2FA security solution requires two independent factors or pieces of information – password and a verification code, to verify identity and privileges of the system admin. This security method is stronger as well as more rigorous than the normal password-alone verification that requires only one factor, i.e. the admin’s password. 2FA is also referred to as Two Step Verification method.

The system admin knows the password (the first factor), and verification code (the second factor) is sent to his registered physical device. This verification code is valid only for a few seconds. If any hacker manages to get the password, then he needs the second authentication factor; verification code, to prove his identity and access UNIX/Linux server completely. In this way, Two Factor Authentication solution ensures UNIX/Linux server security at its peak.

Authentication factors used in 2FA

Below are the possible authentication factors used in 2FA security solution:

  • The knowledge factors (something you know) – username, password, PIN, any other secret information, i.e. question & answer.
  • The possession factors (something you have) – security token, any physical device to receive the code.
  • The inherence factors (something you are) – biometric characteristics such as iris, retina, face scan, voice recognition, fingerprint.
  • Time and Location factors (geolocation).

Two Factor Authentication, as its name suggests, uses any two of the above-listed authentication factors to verify identity of the system administrator. Without the combination of any two of these verification factors, the system admin won’t be able to gain access.

2FA benefits

Some major benefits of Two Factor Authentication security solution are:

  • Greatly enhances the security level by requiring two different pieces of information or factors for authentication.
  • Reduces the security risk associated with the weak passwords that can be easily cracked.
  • Provides an alert in the form of a second factor; verification code, whenever any unauthentic user enters the valid password.

UNIX/Linux server security monitoring

The monitoring includes process activities and behaviour for detecting loopholes. This process helps to provide a unique view of the flow of commands running inside the UNIX/Linux session.

Benefits associated with monitoring are:

Process-based Inspection

It includes the tracking of process and sub-processes flow in real time.

Centralized Management

Centralized control enables the organizations to control, deploy and distribute all their servers in just a single click easily.

Real-time Alert

In case of any security violation like package installations, use of unexpected commands, etc., the real-time activity alert will help the system admin to take some security measures for a better protection.

User Activity Inspection

Any sort of illegitimate tasks that may compromise the UNIX/Linux server security can be monitored.

Intrusion Detection

Inspecting the processes or activities that play a pivotal role in hacking the servers.

What are the best practices for controlling UNIX/Linux account privileges?

Below are these best practices:

Managing UNIX/Linux Accounts

Account creation is an easy task, but disabling or removing unrequired accounts is quite complex for the system administrators. They (admins) must actively manage the accounts for minimizing the security risk to server and enterprise.

Implement Least Privilege

The principle of least privileges is one of the best practices from UNIX/Linux server security point of view. For controlling internal threats, restricting the rights and access of a user to the minimal amount is an important practice.

Minimize the Shared Accounts Use

The system administrators should not share accounts. Limit the application’s privilege on the system.

Notify Malicious Activities

After establishing and implementing logging and audit system, the system administrators must set up automated notification of all the malicious activities. Every major and minor violation needs to be reported by the system admins for a better UNIX/Linux server security against all sorts of the intrusions. In fact, alerting and notification system makes the system admins proactive rather than reactive.

Always remember that a good privileged plan is a key to the UNIX/Linux server security at every step.

What’s the Possibility to Bypass Two Factor Authentication?

Two Factor Authentication security solution, also referred to as 2FA or Two Step Verification, was introduced to resolve the weakness of password-only verification i.e. 1FA (One Factor Authentication) and provide a higher security level to the online accounts and data. Logging in to an account using just a single layer of protection, i.e. the secret password, remains no longer enough from the security perspectives. It is because the passwords can be easily compromised or hacked, the hackers have already made this statement true by hacking a plenty of accounts and sensitive data of the users.

With the evolution of technology, the hackers or attackers have also started adopting the latest techniques and finding ways to compromise 2FA-enabled online accounts. Two Factor Authentication security solution, as the name suggests, uses any two out of the possible three different authentication factors; ‘something you know’, ‘something you have’ or ‘something you are’. As this method requires a unique verification code along with the secret password to verify identity of the user, so there is no or a very little possibility to bypass 2FA. The unique verification code or One Time Password is sent to the registered mobile device of the user, and is valid only for a few seconds.

Guessing the secret passwords of end users is a quite easy task for attackers as compared to gaining access to the mobile phone of the users. It reflects that Two Factor Authentication security solution can’t be bypassed.

Authentication factors

Something you know (knowledge factors) – username, password, PIN.

Something you have (possession factors) – credit & debit card, mobile phone.

Something you are (inherence factors) – biometric characteristics of the user like iris, retina, face scan, voice recognition, fingerprint.

Hacker’s access to your phone, makes 2FA bypass possible

One and only situation that makes it possible to bypass Two Factor Authentication security solution is when an attacker not only knows your secret login credentials; username and password combination, but also has your mobile phone in possession for receiving unique verification code or OTP. Your mobile device acts as the strongest link for you, but becomes weak for the attackers to remove 2FA from your account, or receive verification code via SMS or voice calls. Before you realize that something is wrong, the attackers can have access to your online account and sensitive data.

Protecting mobile device is equally important as your secret password, especially for accounts that are 2FA-enabled. It is because if your secret password gets compromised, then unique verification code sent to your mobile acts as a second layer of security. But, if unfortunately, your mobile device also comes in the wrong hands along with the secret password, then Two Factor Authentication security method remains no longer secure for protecting your digital assets.