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  • Writer's pictureSara Millis

How bad is a Denial of Service Attack (DoS) and how do you prevent it?

Updated: Nov 18, 2022

Whilst Denial of Service attacks (DoS) are not necessarily the most common form of cybercrime, they are on the rise. That’s why it is so important, for cybersecurity reasons, that you understand what they are, how they might affect your business and what you can do to prevent them.

In this article, we are going to focus on all of that so you have one clear guide to learn from.

Image of computer screen with alerts saying "Access Denied"

What is a Denial of Service Attack (DoS)?

Denial of Service (DoS) is a type of cyberattack that renders service provision temporarily or permanently inaccessible to users.

Infographic that shows how a DoS attack works

Typically a DoS attack is performed through a single computer running a program that works through several servers and compromised terminals to flood the internet with service requests directed at a single server target.

The overload that this type of attack causes means that users are unable to access the service system if they are under a DoS attack. High-profile banks or payment gateways are usual targets, but they aren’t the only ones. Any SaaS or e-commerce server could also have potential value to a hacker.

The general threat here is that by disrupting trade, attackers can force temporary or ongoing financial issues for the victim.

When is a DoS attack not a DoS attack?

If the cybercriminal enlists the help of many willing or unknowing online internet users to help them in their attack, then this is called a Distributed Denial of Service Attack (DDoS). Otherwise known as “Hacktivism”.

Want to learn about other types of cybercrime? View our full guide.

How common are Denial of Service Attacks (DoS)?

According to a Security Week 2017 article, research shows there could be as many as 28,700 Denial of Service attacks per day.

Whilst Malware remains the most common type of cybercrime, you can see why authorities and service providers are particularly worried about DoS attacks.

Some cybercriminals may be politically or socially motivated in picking their targets, while others are plain opportunistic. Either way, both types of attackers could be at work during smaller pockets of time, for example by disrupting airline ticket sites during the holidays or targeting bigger retailers during Black Friday sales. Alternatively, they might look at long-term disruption by continuing their malicious software over months with the aim to bring down an institution.

In 2022, DoS and DDoS attacks have become a rising concern as patriotic hacktivism mobilised in Ukraine and Russia, showing a new face of online activism as people found new ways to fight social and political injustice. DoS attacks could in theory be reversed, stopping activism sites from reaching their readers and donations.

How to prevent a Denial of Service Attack (DoS)?

  1. Minimise your points of attack and defend them - this could mean putting your foundation system behind a Content Distribution Network or Load Balancer to restrict internet traffic from coming directly to your database servers. This means you can switch out distribution networks if needed.

  2. Building better firewalls - make sure to add preventative steps for SQL injection attacks

  3. Make sure you have plenty of bandwidth and server capacity

  4. Monitor your traffic to understand what is normal and abnormal traffic - over time this will also help you establish seasonal traffic patterns with server providers for more specific bandwidth provision.

  5. Monitor traffic to establish bad IPs or unexpected geographical traffic

Need help protecting your business against a Denial of Service (DoS) Attack?

Cyberattacks can be crippling for businesses, so it is important to understand when and where your systems are most vulnerable. Today we looked at Denial of Service (DoS) attacks and how they could affect your service or product-based business.

If you need help establishing if your firewall is strong enough to keep you protected then contact us today!


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