Software Tools to Prevent Attacks on Servers and Sites

Software tools to prevent attacks on servers and sites - Plesk

As hackers find more sophisticated ways of accessing your data, security is becoming a day-to-day struggle for businesses. Since 2018, security breaches have increased by 11%. And in the first half of 2019 alone, 4.1 billion personal records were exposed. And losses due to data exfiltration, stolen IP, and ransomware are also accelerating at a fast pace. Although nearly two-thirds of business leaders recognize the increasing security risks, only a small percentage have enough server security and website security.

Being fully protected means having multiple layers of security in place. With each layer addressing a different type of threat – and combining to form an impenetrable barrier. This becomes a difficult task for sysadmins, because just uncovering and blocking individual threats isn’t enough. It’s also important to defend against complex threats and take preventative action all the time.

To effectively manage cybersecurity, businesses outsource and use free and premium security tools. Here we’re going to look at some of the field’s top tools. And explain how they can help you enforce the seven key security layers every business needs to stay secure.

Network Firewalls

Firewall helps Linux server security - Plesk

A firewall is a system that prevents unauthorized access to or from a private network. It’s basically like the door to a house: an outer layer of security that determines what can and cannot enter. Of course, you also need the door to be closed, sturdy, and under your control in order to protect you. Most computers come with inbuilt firewall software, typically enough to shield against viruses, malware, and other unwanted content.

However, default firewalls are generic and limited, and so enterprises regularly use hardware firewalls as well. While the default Plesk firewall provides basic server protection, extensions like Juggernaut further secure your server against today’s threats. Juggernaut features include an SPI firewall, brute-force protection, real-time connection tracking, intrusion detection, and dynamic blocklists. Such features give you extra control and allow you to prevent inappropriate communications. Also, take a holistic view of your network, and even scan encrypted data for threats.

A firewall is considered the first line of defense in preventing attacks on servers. However, it’s not the only measure you should take.

Antivirus Software

Install antimalware/antivirus software

If a firewall is the door to your house, your antivirus software is the door to your bedroom. Whereas a firewall protects unwanted content and threats from getting in, antivirus software protects against threats already in your system. It does this by constantly monitoring files, looking for certain signatures to identify malware, and removing viruses and potential threats.

There’s no such thing as too much protection when it comes to antivirus software. The key is finding a tool that suits your needs while being easy to use, lightweight, and regularly updated. Premium antivirus by Dr. Web is an award-winning virus scanning and filtering software that protects mailboxes from many types of malware. Including viruses, worms, and trojans.

More great options are the Plesk Premium Antivirus or Kaspersky Antivirus extensions. Both extensions scan server mail traffic in real-time. But only Kaspersky allows fine-tuning and filtering of specific file types from attachments. Then there’s ImunifyAV – the leading malware-scanning tool. It ensures you keep malicious code away through antivirus, security and domain monitoring, blacklist status check, and one-click malware removal.

Endpoint Detection and Response (EDR) Software

EDR software - end point detection software - Plesk

EDR is a technology that addresses the need for continuous checking of file signatures. Checking for signs of malignancy and rapid responsiveness to advanced threats.

Whether it’s a Mac, PC, or a server, a good EDR system can detect suspicious activity running on any endpoint. This is especially important as even if a hacker has entered your system, for the hack to have a serious impact they must be able to siphon information out of your network. EDR software prevents this from happening by essentially placing compromised devices in quarantine, so no intel can be sent/received.

EDR is an advanced step in server security and so it typically comes at a cost. Kaspersky EDR provides full endpoint protection, from automatic threat blocking to complex incident response. It’s particularly popular for its comprehensive visibility across corporate networks and capacity to discover, prioritize, investigate, and neutralize advanced threats.

Anti-Phishing Tools

phishing - anti-phishing tools - Plesk

Phishing is a way of finding and gathering personal information using deceptive emails and websites. Techniques typically involve persuading people to click on malicious links by suggesting they are important and/or safe. It happens mostly through messaging platforms like email and chat apps. Built-in spam filters block most generic phishing attempts sent out to thousands of people. However, targeted phishing attempts, which may target specific individuals or organizations, can be harder to block.

Phishing is a particularly tricky form of cyberattack to protect against and it can appear so real. Neutralizing such scams, which have tricked even the savviest of CEOs, requires special anti-phishing tools. Warden Anti-spam and Virus Protection is a paid extension designed for power users and service providers. Besides providing high-performance and simple antivirus tests, it also offers support for nearly 30 SpamAssassin plugins. And is therefore one of the most robust anti-virus and anti-spam tools around.

Encryption Tools

encryption tools - Plesk

Encryption tools are software that use cryptography to prevent unauthorized access to sensitive information. It works by encoding data from “plaintext” into “ciphertext”. This process turns unencrypted information into an encrypted form for which you need a key to decode. Typically a password, making it harder for outsiders to access.

There are two main types of encryption: software and hardware encryption. Software encryption is more selective and focuses on encrypting individual files and folders. Hardware encryption involves encrypting entire devices.

Linux users will be used to connecting to servers using SSH keys. SSH (Secure Shell) keys are access credentials used in the SSH protocol. A secure and widely used standard for strong authentication, secure connection, and encrypted file transfers. Using SSH keys is more convenient and secure than traditional passwords.

From Plesk 12.0 onwards, you can use SSH Keys Manager to effectively manage SSH keys from the Plesk UI.

Specific Server Security Tools

specific server security tools - server security software - plesk

Some of the most popular Plesk extensions are those which improve your server’s security. Here are some of the most powerful ones which help combat server threats.

Sentinel Anti-malware

Sentinel Anti-malware is a scanner that combines the open-source principles from Linux Malware Detect and ClamAV. This extension especially serves power users and service providers who want to ensure they have protection from a variety of malware.


This premium extension (free trial for 30 days) protects Linux servers against critical vulnerabilities. Mainly by automatically installing security updates to running kernels. This avoids rebooting servers and planning scheduled downtime for your customers. And it also ensures kernels are updated within hours of patch releases for uninterrupted security.


The BitNinja extension prevents 99% of malicious attacks. This can consequently reduce your server alerts and customer complaints by just as much. It actually provides protection against nine different aspects of attacks – including malicious port scans and infections. You can even set it up and start automatically protecting your server in as quick as five minutes.


Cloudbric provides award-winning enterprise WAF and DDoS protection. Firstly, it has a threat detection system for real-time security against hacking attempts, website defacement, DDoS attacks, and spambots. Secondly, you can activate it with one click and try it for two weeks for free. While also benefiting from Cloudbric’s free and expert technical/security support.

DDoS Protection by Variti

DDoS Protection by Variti protects sites from DDoS – one of the most popular online attacks. As well as other types of sophisticated bot attacks. It does this by analyzing real-time traffic and passing it through a distributed network of VARITI filtering nodes. This extension is ideal for companies that depend on online traffic protection for their business.

Atomic Secured Linux

The Atomic Secured Linux extension provides the same level of protection that typically comes with an expert security team. It can prevent, detect, and respond to today’s greatest cybersecurity challenges. In particular, it features host and kernel intrusion prevention systems, brute force protection, and automated malware removal.

(D)DoS Deflate Interface

(D)DoS Deflate Interface is a lightweight shell script that helps deflect DDoS attacks automatically. The script runs in the background, blocking incoming connections from multiple IPs from which connections exceed the configured threshold. And above that – It’s simple to install and operate.

Penetration Testing Software

Password policy vs Hacking Techniques

Penetration testing software is the final line of defense in your security arsenal. Professional ethical hackers simulate a cyberattack (penetration testing), allowing enterprises to find weaknesses in corporate networks long before attackers do.

Rather than just software, penetration testing is often handled by human experts. Once your systems are in place, this added level of security helps you answer two questions in particular. First – does your security system have enough layers? And second – do those layers actually work?

In penetration testing, certain tests can, however, run autonomously. For example, Burp Suite’s vulnerability scanner autonomously crawls an enterprise’s web presence in search of common security holes. Including cross-site scripting, SQL injections, and volatile content. Admins can schedule Burp scans and see the resulting analysis in the form of detailed visual maps. Allowing for the ultimate control and protection of your business’s data.

How tight is your server security against attack? Do you use these tools or different ones? Let us know in the comments below!

Three New Web Application Threats and their Solutions

Web Application Threats

Malicious users will try to access your web application without your consent. Therefore, you should implement the necessary security features to protect yourself from new web application threats: Spoofing, information disclosure and data tampering. Let’s see how together we can mitigate threats using Plesk security tools.

1. Spoofing


Spoofing is one of the modern web application threats, despite security measures you may implement back-end to protect users’ credentials. It’s pretending to be someone or something other than yourself. And it can happen in many ways.

Fake User Authentication

Attackers can create a fake login page similar to that of a web application to trick users to log in. So that they can steal users’ login credentials. For spoofing, attackers can even use SET (social engineering tools) to clone a login page of a popular web application.

Fake User Authentication

Cross-Site Request Forgery (CSRF)

Cross-site request forgery tricks a web browser into executing an unwanted action. Like transferring funds from one account to another account in a web application where a user is already logged in. Attackers usually use social engineering tricks to implement CSRF by sending links to authenticated users on social media. In other words, those already logged into a web application.

Then unsuspecting users end up sending a forged request to a server on behalf of a malicious user. Though it’s quite difficult to prevent this, below is how you can mitigate cross-site request forgery.

How to Prevent Spoofing Threats

  • Implement an SSL/TLS Certificate

To defend against authentication spoofing, make sure that a web application such as banking portal has an SSL/TLS certificate in place. Plesk lets customers get these certificates for free in just a few clicks.

Spoofing Threat Prevention

Even less technical customers can use the Let’s encrypt extension on Plesk platform to easily create SSL certificates for their domains. And make it difficult for attackers to create spoofing attacks.

Generate Random Tokens  

Otherwise, to prevent forged requests, you can even use tokens to validate GET/POST requests from users. For example, to enable csrf protection in Flask-based applications, you can use the Flask extension CSRFProtect by enabling it globally.

from flask_wtf.csrf  import  CSRFProtect

csrf =  CSRFProtect(app)

Alternatively, you can use FlaskForm to prevent forgery request in flask web applications. However, the standard way of preventing CSRF threats in Java or PHP web applications is by implementing an anti-CSRF token only visible to the user’s browser and web application inside a session variable with a request. If the value of the session variable and hidden form field match, the user’s request is accepted.

2. Information Disclosure

Information Disclosure Threat

Allowing unauthenticated users to access documents restricted to only authenticated users can be defined as information disclosure. The following describe diverse ways information disclosure can take place.

IDOR – Indirect Object Reference

IDOR attack is possible when a web application provides direct access to the object based on a user-supplied input. It makes it possible for unauthorized users to access resources restricted to them. Let’s assume user A logs in to a banking web portal, then the user is redirected to the following url:

In this case, 00012345 is user A’s account number. If the user wants to access other customers’ account details, user A just needs to change acc=00012345 to acc=000112367.

Therefore, the above action allows a user to access account details of another user without the owner’s consent.

How to prevent

There are different ways to prevent indirect object reference.  Another way to prevent exposure of real identifier to an internal object, like database record, is using a salted hash value to replace the identifier.

SQL Injection

SQL injection is one of the most common ways malicious users use to disclose information restricted from public view.  Attackers can send commands such as SELECT to download an entire database, CREATE to create new users in the database or UPDATE to modify accounts.

How to prevent

You can use prepared statements to prevent an attacker from changing the purpose of a query. A prepared statement separates the query from the data. Thus, the data submitted by an attacker can’t be used to modify the query. Moreover, for flask developers, you can also prevent SQL injection by using SQLAchelmy to interface with the database. It comes with features to prevent SQL injection threats.

3. Data Tampering

Data tampering is the act of intentionally modifying data through unauthorized channels. There can be two states of data: in transit and at rest. In both instances, malicious users can intercept and tamper with data. Here’s how data tampering can take place.

Parameter Pollution

Let’s assume a web application allows users to send sensitive data. Like login credentials or transact funds via GET and POST methods. In this case, an attacker can tamper with URL parameters and modify data.

To prevent parameter pollution threats in a web application, you need to encode user-supplied input whenever a user sends a GET/POST request to the backend server.

Session hijacking

Session hijacking

Session hijacking is also another type of attack where malicious users steal session cookies. Each user is assigned a session when they log into a web application. The sessionID is usually stored in a cookie. Attackers use session hijacking to modify data in transit from the client (web browser) to the web server.   

How to prevent: Generate Random Session IDs.

Moreover, Plesk also provides loads of security extensions for customers to prevent or mitigate threats not mentioned above. For example, the Sucuri Security Scanner extension on Plesk to remotely detect website security issues and weaknesses in the source code.

Sucuri Security Scanner on Plesk - Screenshot

Avoiding these new web application threats

Having said that, don’t just rely on Plesk extensions to protect web applications from web attacks. You also need to use your own secure coding practices to mitigate these threats. So, equip yourself, but stay vigilant.