How To Stop Denial of Service Attacks in 5 Steps


Denial of Service attacks ( DoS attacks) are among the most feared threats in today's cybersecurity landscape. Difficult to defend against and potentially costly, DoS attacks can cause outages of websites and network services for organizations large and small. DoS attacks can also be lucrative for criminals, some of whom use these attacks to shake down businesses for anywhere from thousands to millions of dollars.

DoS Attacks vs. DDoS Attacks

So how do you stop denial of service attacks?  First foremost, it’s critical to understand that not all cyber-attacks are created equal. DoS and distributed-denial-of-service (DDoS) threats come in various flavors, with some targeting the underlying server infrastructure. Others exploit vulnerabilities in application and communication protocols, such as SSL-based attacks.

Unlike other kind of cyberattacks, which are typically launched to establish a long-term foothold and hijack sensitive information, denial of service assaults typically do not attempt to breach your security perimeter. Rather, they attempt to make your website and servers unavailable to legitimate users. In some cases, however, DoS attacks also used as a smokescreen for other malicious activities and to take down security appliances.

The differences between DoS attacks and DDoS attacks are substantive. A DoS attack leverages a single computer and Internet connection to flood a target with fake requests (such as TCP/UDP packets) or exploit a software vulnerability. The point is to overload the targeted server’s bandwidth and exhaust its resources (RAM and CPU).

In many respects, a DDoS attack is similar to a DoS attack, but is launched from multiple connected devices that are distributed across the Internet. Therefore, the main difference between DDoS attacks versus DoS attacks is that the target will be overloaded by hundreds/thousands of requests in an attempt to saturate it with huge volumes of traffic.

Be Prepared

So how do you prevent denial-of-service attacks? You have to be prepared. According to Radware’s 2016 – 2017 Global Application & Network Security Report, forty percent of global respondents still lack a formal incident response plan. How can you effectively stop denial-of-service attacks if you don’t know which resources will be available at the moment of attack? For many organizations, dealing with a certain threshold of low-level attacks has become commonplace. But some actually cause serious disruptions that pose a potential threat to the business—and must be handled immediately. How can you tell which is which?

How To Stop Denial of Service Attacks Step 1 – Map Your Risks

You may be spending significantly on penetration testing and the latest technology for endpoint protection all the way down to BYOD mobile phones. Even so, you may be overlooking critical gaps. To stop denial-of-service attacks, consider everything. Use a bidirectional process where you draw your organization from the inside out, understanding your current information security architecture and looking for vulnerabilities. Consider who might want to hurt you, why and what means they may have to do so. These actors may include hacktivists, ransomers, competitors or even disgruntled insiders or customers.

How To Stop Denial of Service Attacks Step 2 – Understand the Impact

To effectively stop denial-of-service attacks, you have to understand the potential impact. Some costs can be easily added to the equation: What’s the cost of a minute of downtime? An hour? Are there any legal fees or compliance fines you would face if compromised? What would be the daily cost of investigating an attack (factor in-house labor as well as the costs of executives’ attention and technology partner services)?

Other financial impacts are harder to pin down. A prime example is reputational impact, which can vary depending on the severity of the attack and how much time your organization spends in the headlines.

How To Stop Denial of Service Attacks Step 3 – Prioritize Critical Missions

After estimating the different impacts, it becomes easier to determine what is essential for the organization to continue functioning. Prioritize business procedures and processes, engaging executive management both for their input as well as their endorsement and resource allocation. As much as possible, use key performance indicators to help measure the efficiency of the incident response plan.

How To Stop Denial of Services Attacks Step 4 – Choose Your Squad

Once you have defined the critical processes, identify the dedicated personnel to run them. The incident response plan cannot be the sole purview of the cyber security team; other key players in the organization must also know how to orchestrate critical missions when enmeshed in a crisis. For the information security aspects of the breach, your team must include the best security experts in the organization. They should not only know how best to configure the product, but also know how to think like a hacker.

The “textbook” incident response team has system administrators who are very familiar with IT resources and how to backup data; network administrators who know network protocols and can dynamically reroute traffic; and information security personnel who know how to thoroughly track and trace security issues as well as perform post-mortem analysis of compromised systems.

How To Stop Denial of Service Attacks Step 5 – Test, Revise, Adapt

An incident response plan is never “complete.” After all, the threat landscape is dynamic. So is every business and its network, information and collection of vendors it relies on to support operations. When a crisis occurs, there is no room for error; your response must be rapid and decisive. To prevent denial-of-service attacks in the future, routinely stage “emergencies” and practice responding to them. In doing so, your organization will develop a methodology that fosters speed and accuracy while minimizing the impact of unavailable resources and potential damage should an actual crisis occur. These simulations should involve not only the cyber security response team, but also those responsible for the communications plan, along with your technology partners, service providers and relevant executive leaders.

In security, it is generally wise to invest in prevention over detection. With cyberattacks likely to impact every business in some capacity, preparation is a major step toward mitigating successfully and minimizing the financial, reputational and legal havoc an attack can wreak.

Do you want to learn how to protect your online business by preventing DDoS attacks? Contact Radware today