DDoS Attack Explained With 5 Tried And Tested Methods for Mitigating it

If you want some help then surely you haven’t planned to overcome DDoS attacks. However, it should be as soon as possible. In this article, we’re going to cover what is DDos attacks are and how to prevent from DDoS attacks.

Nowadays, Distributed Denial of Service (DDoS) is the most used form of cyber-attack. Various organizations are facing issues of this type, having their websites unavailable for legitimate users. A DDoS attack in cyber security results in major disruptions to the users that last from a few seconds to even some hours or days. In the past, it was an activity done for fun, however, the situation has become more complicated nowadays. 

The IT industries have seen a logarithmic increase in DDoS attacks in the last few years. The upward trend is ever continuing even now, putting the certified ethical hacking courses and various SIEM tools skills in high demand.

InfoSecurity Magazine mentioned in their report that: about 2.9 million DDoS attacks happened in 2021, which is a 30% hike compared to the previous year. 

DDoS Attack

In recent years, many top companies have faced Distributed Denial of Service attacks which have impacted them for a significant amount of time. 

• In February 2020, Amazon Web Services (AWS) faced the issue and kept its incident response teams occupied in overcoming the situation. It has impacted several days which affected their customers worldwide!
• In February 2021, the top Cryptocurrency exchange company (EXMO) suffered from a DDoS attack that destroyed the enterprise’s availability over the internet for almost five hours.
• Recently, Australia and Belgium also experienced a significant attack of one of these kinds.

What is DDoS Attack?

DDoS aims to disrupt a particular website or server by sending it fake traffic in high amounts. It is done so that the server may not be able to cope with it. This prevents legitimate traffic from reaching the final destination of any website or application. These kinds of attacks cause financial damage to the enterprise and affect users also. 

But what does DDoS stands for? 

DDoS stands for Distributed Denial of Service. A DDoS attack happens when a vector threat appears in the system from multiple remote locations to affect any enterprise’s daily operations. 

Generally, these attacks focus on damaging the network components (e.g., routers, firewalls, ISPs, applications, and data centres).

DoS vs. DDoS Attacks: What’s the Difference?

• DoS (denial of service) attacks are very similar to DDoS(distributed denial of service) attacks. However, DoS have a single source to send the malicious traffic and DDoS has several distributed systems to send malicious traffic.

• DoS attacks can be identified easily and so you can detect the real traffic and fraud traffic. While in the case of DDOS, it becomes difficult to find which traffic is the real traffic and which are the fake connections.

• The firewall can see that a high number of connections are coming from any specified address in DoS. Then, it will block that IP address. So, blocking DoS is easy for the firewall because it is executed by only one system. It becomes difficult for the firewall to block malicious SYN packets in DDoS attacks while it is easy to block the malicious server in a DoS attack. 

Attacker’s Motive behind any DDoS Attack

The attacker’s motive is to make the targeted website(or the targeted server’s operations) unavailable for some specific time. An attacker can execute DDoS attacks in various ways. Usually, they use botnets that are the servers connected to the internet and are in control by them. They just disrupt the normal behaviour of the organization’s services that denies access to legitimate users.

So, the users will switch to some other website. Attackers do this by sending a high number of SYNchronize(SYN) packets to the targeted site. Then the site sends a SYNchronize-ACKnowledge(SYN-ACK) packet back to the attacker’s IP address. 

This is the method of stabilizing the connection in the TCP. Now, if the legitimate user tries to access the website, it will show an error saying your request is timed out. This is because the target server becomes so busy dealing with attackers’ requests that it doesn’t get time to respond to real users. This causes the target server to stop responding resulting in a longer delay. It fulfils the hacker’s motive.

How attackers actually plan it

You can see some websites out there on the internet where a cybercriminal runs DDoS as a service. You can buy it for some specified time starting from a few seconds. Attackers send the malware emails attachments. And you would never know that the link attached in the email has installed malware in your system. This will then shift all your operational controls to the attacker’s command server.

Eyes on the Enemy: Identifying DDoS Attacks

For identifying these types of threats, you must know how to recognize a specified pattern. Being able to spot any repetitive pattern is the key to identifying DDoS attacks. Artificial intelligence and other automated software are generally used by companies as helpers. However, they require a skilled cyber security expert also to deal with these high threatening attacks. Professionals often try to see these below-mentioned warning signs to know if it is taking place:

• Negative reports from the network components and mitigation devices.
• Customers report slow or unavailable services for an instant.
• Employees experiencing speed issues to work in the same connection.
• Multiple connection requests come from a single IP address in a short amount of time.
• You receive a service unavailable error even when you are not performing any maintenance work.
• Ping requests to show requests timed out due to Time to Live (TTL) timeouts. 
• Logs display an abnormal hike in the traffic.

Types of DDoS Attack

All of the DDoS attacks are aimed to flood a system with high traffic. However, the strategy used can differ based on the types of DDoS attacks. The three kinds of DDoS attacks in cyber security are:

• Application-layer attacks.
• Protocol attacks.
• Volumetric attacks.

These three kinds of attacks employ different techniques. Also, a skilled hacker can use all of these three mentioned strategies for a denial of service. 

1. Application-Layer Attacks

An application-layer DDoS attack disturbs only a specific application and not an entire network. A malicious attacker generates voluminous HTTP/HTTPS/SMTP/DNS requests that damage the target server’s workings. It is also known as a layer 7 attack. It is mostly a challenging job for the security team to prevent this type of threat.

1. Protocol Attacks

Protocol DDoS attacks are attacks on network layers that damage the protocols or procedures controlling internet networks. While an application-level threat targets a single app, the protocol attack targets to slow down the entire network.

The two types of protocol-based attacks are:

• SYN floods: This damages the networking by sending a high number of TCP requests with fake addresses. The hacker exploits the handshake procedure and eventually leads to crash the server.

• Smurf DDoS: The attacker uses malware for creating a network packet and sends it with a fake IP address. This generates an infinite loop of sending ICMP ping messages that also crashes the system. 

2. Volumetric Attacks

A volumetric attack looks for the target server’s available bandwidth for creating network congestion. The high traffic blocks the real users from accessing the website or the application with false data requests. These depend on botnets to cause traffic spikes and use all the bandwidth available.

The most common volume-based threats are:

• UDP floods: These attacks use a high amount of IP packets with UDP protocols to overload ports on the target host. 
• DNS amplification: This attack redirects a high number of DNS requests to the targeted system.
• ICMP flood: This attack uses ICMP fake error requests to clog the network’s bandwidth.

5 Best Practices for Mitigating DDoS Attacks

Now, we will discuss how to prevent DDoS attacks. Let us find out the important measures to be taken to stay away from these types of attacks. 

1. Improve Network Security 

Network security is essential for preventing any kind of Denial of Service attacks. The ability to find a DDoS attack’s future probability is vital for controlling it. You can follow the given steps for securing your network to protect it from DDoS attempts:

• Install necessary tools to protect your network infrastructure and applications. Firewalls are an essential device that acts as a traffic-scanning barrier.
• Threat monitoring systems and tools like anti-malware and anti-virus software can detect and remove malware and viruses.
• Make sure that the network endpoints (e.g, laptops, mobile devices, etc.) should not become an entry point for any malicious activity.
• Web security tools can also be used to remove web-based threats and block abnormal traffic.
• Tools can help you keep track of your network traffic and prevent spoofing by matching origin addresses and source addresses. 

Update your systems and networks regularly to fix any bugs or issues. In the case of a DDoS attack, it is very difficult to mitigate it after the attack. Hence, detecting threats in advance is the only best option. 

2. Design a Powerful Architecture

Ensure that your data servers have various networks and paths. Your IT infrastructure should not have a single point of failure that could be easily exploited by the attacker. Relying on different distributed servers makes it difficult for the cyber-attacker to harm all the devices at the same time. So, other servers remain unaffected if the hacker succeeds in the DDoS attack on a single hosting device. This will ensure to slow the downtime as the resources would be shared at different servers.

Having a static version of your website can also help you a lot. This would be a place to send the extra traffic when your server goes down. A static version requires less processing power and bandwidth so that the load will be minimum.

The content delivery network(CDN) can also be used to share the server’s load equally. It can take on the extra traffic until the targeted server is back with its functionalities.

3. Look Out for the Warning Signs

Remember, If your team of network security is able to find the patterns and some common traits of these kinds of attacks, timely mitigation actions can manage the damage. Also, you should educate the entire staff on a security awareness training program. This will make the team members pick up the DDoS attack warning signs if any. 

Some common signs of a DDoS are:

• Showing poor connections.
• Slow performance speed.
• Occurring crashes.
• Sudden changes in traffic coming from a single or a specified group of IP addresses.
• An unusual hike in traffic from users with a common geolocation or web browser version. 

4. Create a DDoS Response Plan

Your IT team should make an incident response plan. It would let you handle DDoS attacks in cyber security effectively. This plan should cover what your team does if and when a cyber-attack happens. It may be:

• Clear and step-by-step instructions on reacting to an attack.
• How to manage enterprise workings.
• Go-to staff members and key stakeholders.
• Escalation procedures.
• Team responsibilities.
• A checklist of all essential tools.

5. Report to Internet Service Provider

Contacting your ISP( internet service provider) is a great way to block the hacker server’s IP address.  They have trend-based mechanism devices such as radware and Centurylink that help protect against these attacks. If any unusual spike is seen from any device, ISPs are able to block them. 

ISPs mitigation practices often come with a low-cost add-on. They leverage bandwidth by using different data centres to tackle volumetric attacks. They are excellent in transporting packets and are solution-rich where bandwidth is the key. 

Do Not Ignore:  The DDoS Threat

DDoS Attacks are high threats to a network or device. These are ranked one of the top 5 threats of cyber security. With the increasing number of attacks, they are becoming more dangerous as well. Experts have predicted the average number of threat attempts will count as 16.4 million annually by 2024. This number indicates that nearly each and every enterprise will face a DDoS at some point. Thus, preparing for DDoS attacks should be the top priority for every business. 

Read our next blog The complete guide of Why is Threat Intelligence Important?

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