How DDoS Works: A 2021 Guide
Distributed Denial of Service (DDoS) is usually performed by bombarding the targeted computer or resource with unnecessary requests to overload systems and prevent some or all legitimate requests from being completed.
The traffic overloading the target in a DDoS attack comes from a variety of sources. This option effectively makes stopping the attack by blocking a single source difficult. A DDoS attack is a set of cybercriminal operations intended at compromising a company’s equipment and client operations.
With the average cost of downtime hitting $336,000 per hour, businesses must secure themselves from the DDoS perspective to reduce their threat surface.
So, what is a DDoS attack? Let’s look at Wikipedia:
In computing, a denial-of-service attack (DoS attack) is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to the Internet. Denial of service is typically accomplished by flooding the targeted machine or resource with superfluous requests in an attempt to overload systems and prevent some or all legitimate requests from being fulfilled.
In a distributed denial-of-service attack (DDoS attack), the incoming traffic flooding the victim originates from many different sources. This effectively makes it impossible to stop the attack simply by blocking a single source.
In simple words, a DDoS attack is the actions of cybercriminals aimed at disrupting the performance of a company’s infrastructure and client services.
The average cost of a DDoS assault is $120,000. Furthermore, a huge corporation may end up paying more than $2 million.
DDoS attacks centered on ransom and extortion have been on the rise. Many clients wind up paying hackers a substantial price only to prevent or stop the attack. Furthermore, even after paying, there is no guarantee that the hackers will keep their word.
Meanwhile, someone can purchase DDoS attacks for only $10 USD per hour. This substantial difference in the cost of purchasing a DDoS attack versus the effects of a DDoS attack makes them fairly common.
A web service becomes unreliable or, in the worst-case scenario, completely inaccessible during a DDoS attack. One will notice either a large number of requests hitting the domain or a large volume of unsolicited traffic that users do not expect to see.
Every DDoS assault is unique and has its objectives. One episode can last as little as 5 minutes, while others can persist for days. How long an attack can last depends entirely on the individual attack.
A dispersed denial of service attack is an attempt to cause a server to slow down or crash completely. It aims to disconnect users from a server or network resource by flooding it with service requests. While a single attack computer and one victim are involved in simple denial of service, distributed denials of service rely on legions of infected or bot computers capable of performing tasks simultaneously.
To identify a botnet, one must first identify the source of its attacks. In most situations, these are computers and IoT devices like IP cameras and home WiFi routers. Still, people can manipulate these gadgets even though they get infected with malware. A Botnet has all of these devices.
A hacker creates a botnet to take advantage of a flaw in a system and turns it into a botmaster. The botmaster looks for other computers that are susceptible and infects them with malware. When a sufficient number of devices have gotten infected, the hacker instructs them to launch an attack; each machine sends a torrent of requests to the target server or network, overloading it and causing slowdowns or failure.
A common website can be DDoS-ed in multiple ways. But there are two common options:
- Volumetric attack – you will receive a high amount of unwanted traffic.
- Application attack – you will receive a high number of requests to your website.
According to statistics, the ratio between volumetric and application DDoS is about 50/50. So, it’s quite obvious that the owner of a web service should be prepared to mitigate both types of attacks.
A volumetric attack is one of the cheapest and easiest types of DDoS attacks. The main goal of this attack is to hammer the internet link to your web service. Let’s say, you have a website and an uplink of 1gbps. In case of this type of attack – you will receive 10gbps of incoming traffic or even more.
How will it affect your website?
It will become unavailable. Because your internet link is congested, all requests (including both regular user’s requests and volumetric attacks) can’t be delivered to your website. In most cases (but not always), these attacks can easily be mitigated with the help of your ISP. This attack is trying to congest your Internet link with UDP flood or DNS or NTP amplification.
Application Layer attacks are more complex. The main goal of this attack is to make your web server defunct. Before an attacker can use an application layer attack, they need to conduct a fairly in-depth analysis of your website. Let’s say, you have a webpage that requires more computer resources on your server than other web pages (e.g., some analytical info, which should be calculated on your web service). Every request to this page will add some load to the CPU on the server. So, generating quite a lot of requests to this page – will congest your computing capacity. The effect of this attack? Slow page response to the clients or complete inaccessibility of the website.
Volume-based attacks and application-layer attacks, while the most common types of DDoS attacks are not the only types of DDoS attacks. Here are a few of the more specific types of DDoS attacks that are less common, but still occur:
- ACK Flood: They recognize session requests that were never received and do not exist. Unnecessary lookups in the state tables get generated by packets that do not correspond to any existing session on the victim’s firewall or any security device along the path.
- DNS Flood: A DNS Flood makes falsified DNS requests to the target network at a high packet rate and from a wide range of source IP addresses. The victim’s DNS servers reply to all faked queries since they appear authentic, and the massive requests might overload their capacity.
- Ping Flood: In a Ping Flood, an attacker sends many fake ICMP echo request packets from random source IP ranges or the victim’s IP address. By default, most network devices respond to pings by sending a reply to the source IP address.
In just the first half of 2021, a recorded 5.4 million DDoS attacks occurred representing an increase of 11% compared to last year which were already record numbers of DDoS attacks.
This pattern is likely to persist. Within an attack, another tendency is the employment of several attack paths. This pattern alters the impact of DDoS assaults on businesses and increases their risk.
The first known DDoS attack occurred in 1996 targeting an Internet Service Provider in New York. This attack utilized an old form of a DDoS attack called an SYN attack. The attack overloaded the ISP by flooding the network with SYN packets resulting in about 36 hours of downtime. These early forms of DDoS attacks were rudimentary and uncommon until the year 2000.
In 2000, DDoS attacks were beginning to develop into a more serious threat. The first major attack occurred in February of 2000 attacking Amazon, eBay, Yahoo, Dell, CNN, and FIFA. With this attack, the world realized how easy DDoS attacks were to conduct as a young teenager from Canada took down these major corporations using a volume-based attack.
As these attacks began to grow in frequency and severity, the tactics used for DDoS attacks also grew. Eventually, in 2007, DDoS attackers began targeting nation-states throughout Europe. These attacks continued to occur and in 2009, DDoS attackers began taking down major U.S. government sites including the Pentagon, the Department of Defense, and even the White House. While the source of these attacks is still unknown, they were believed to have occurred in North Korea.
2016 was the next major advancement in DDoS attacks with the use of botnets. Then, in 2018, these DDoS attackers realized they could ransom the sites they take down through DDoS to begin earning money. To this day, DDoS attacks continue to be a threat to any online infrastructure.
In the modern-day, almost anyone can perform a DDoS attack by hiring hackers. These underground hackers put their DDoS services up for sale on encrypted marketplaces typically found on the darknet. The ease of access to DDoS attacks makes them a commonplace threat.
Hackers use a variety of methods to conduct DDoS attacks including volume-based attacks, application-layer attacks, ACK flood attacks, DNS flood attacks, and Ping flood attacks.
Political motivations, revenge, financial interests, criminality, or even activism can be factors in DDoS attacks, prompting many to blame governments, terrorist groups, angry employees, and even thrill-seeking lone hackers.
Attackers use DDoS assaults for a variety of reasons:
- To interrupt the operation of a service, such as online lessons or tests.
- For extortion.
- As a weapon against rivals.
- To divert attention away from the attack to deploy ransomware infections and steal company information.
DDoS attackers combine a variety of methods to avoid detection and remain anonymous. These tactics include spoofing, reflection, and amplification. Spoofing allows the attacker to provide fake source addresses so the actual source address cannot be detected. Reflection utilizes thousands of different servers to mask the origin of the attack. Amplification sends a single forged packet to a website that causes legit services to send an overwhelming number of replies to the victim’s network or website.
Almost always – yes, but in some cases DDoS attacks can also be legal. Why and when can it be legal? Sometimes you want to receive a DDoS attack to understand how good you are protected from these types of attacks. Or, you have your own solution and want to test it. There are some companies which can make a DDoS attack to your web service and provide a full report after. But all these attacks (time, destination, duration, capacity) were approved by all parties before. If the attack is not approved by all parties before the attack takes place, it is illegal.
Yes, DDoS attackers can go to jail under the Computer Fraud and Abuse Act which can result in up to 10 years of jail time.
No, but someone can attack your site every week for a few hours or even more often.
Every DDoS attack costs money. Volumetric attacks are cheaper, while application attacks – are more expensive but more difficult to stop.
Depending on the ISP you are using, it can help you with the DDoS attack or make it even worse. What does that mean? Well, a common ISP has a lot of clients. In case of a massive DDoS attack, an ISP may not be capable of blocking the attack giving the attacker the opportunity to blackhole your web service. ISP need to choose between:
- Keep trying to mitigate this attack, while it affects other clients
- Turn off you service (disable from the Internet)
And to be honest, when an attack is massive, most ISPs will choose option 2, just to make other clients available.
A firewall cannot stop a DDoS Attack. Admins built firewalls to protect networks from a range of security threats, and they still do, but there are gaps in DDoS and malicious server targeted attacks.
A VPN masks the IP address and keeps the actual location hidden by routing data traffic through remote servers. One can switch to remote servers at any time using a VPN, so even if attacked, the business does not have to halt.
Yes, changing your IP and DNS name can stop a DDoS attack.
DDoS assaults cannot steal information from website visitors. A DDoS attack’s main objective is to overwhelm a website’s resources. DDoS assaults, on the other hand, can be used for extortion and blackmail.
Yes, someone can DDoS you with just your IP address. With your IP address, a hacker can overwhelm your device with fraudulent traffic causing your device to disconnect from the internet and even shut down completely.
A DDoS mitigation plan in place can mean the difference between hours or days of disruption for an organization and a smooth and prompt response that keeps things running smoothly.
DDoS Protection should be:
- Scalable and Volumetric
- Agile and Cost-Effective
- End-User Friendly
- IoT Ready
Web application firewalls allow users to defend against web threats in seconds without slowing down the website. Contact GlobalDots now to ensure your safety!
It is important to ensure system safety to avoid compromise. Not all DDoS defenses are created equal, and tailoring them to the specific demands of a company takes experience. GlobalDots relies on years of experience to create a DDoS protection strategy specific to your business.