Everything about Distributed Denial of Service (DDoS) Attacks

Attacks by a distributed denial of service (DDoS) are now commonplace. A DDoS assault can impede or disable an organization's online services—email, webpages, anything that addresses the internet—whether it be a small non-profit or a giant global company. 

 

DDoS assaults can target the most valuable consumers and pose a threat to the infrastructure that ensures network and service availability for all of the tenants, subscribers, and customers of data centers, colocation facilities, hosting companies, and other service providers.

 

A successful DDoS attack has the potential to substantially harm a brand's reputation and result in financial losses of hundreds of thousands or even millions of dollars. DDoS attacks are also occasionally used to divert cybersecurity activities from illegal behavior like data theft or network intrusion.

 

Denial-of-service attacks: What are they?

 

When a hostile cyber threat actor prevents authorized users from accessing information systems, devices, or other network resources, it is said to be a denial-of-service (DoS) attack. Services that rely on the impacted computer or network, such as email, websites, online accounts (such as banking), or other services, may also be impacted. 

 

By overwhelming the targeted host or network with traffic until it becomes unresponsive or fails, a denial-of-service condition is created, blocking access for authorized users. DoS attacks can cost a company money and time while its services and resources are unavailable.

 

Also Read | Everything About Cybersecurity Threats, Attacks and its Types

 

What is a DDoS attack?

 

Denial of service (DoS) attacks include distributed denial of service (DDoS) attacks as a subclass. A distributed denial-of-service attack (DDoS) is a malicious attempt to obstruct a server, service, or network's regular traffic by saturating the target or its surrounding infrastructure with an excessive amount of Internet traffic. 

 

A distributed denial of service (DDoS) attack is when one or more attackers try to prevent the delivery of a service. This can be done by preventing access to almost anything, including networks, applications, servers, devices, services, and even individual transactions inside applications. 

 

A single system sends harmful data or requests during a DoS assault, whereas several systems participate in a DDoS attack. By using numerous compromised computer systems as sources of attack traffic, DDoS attacks are made effective. Computers and other networked resources, like IoT devices, can be exploited by machines.

 

When viewed from a distance, a DDoS assault resembles unexpected traffic congestion that blocks the roadway and keeps ordinary traffic from reaching its destination. These attacks typically work by flooding a system with data requests. 

 

This can involve flooding a database with queries, or it might involve sending a web server so many requests to display a page that it crashes under the load. As a result, the amount of CPU, RAM, and internet bandwidth available is exceeded.

 

The effects could be as minor as service disruptions to the complete shutdown of websites, programs, or even entire organizations.

 

Also Read | What is a Botnet & How to Protect Yourself Against Botnet?

 

How do DDoS attacks work?

 

Any DDoS assault is centered on DDoS botnets. A botnet is made up of hundreds or thousands of devices that have been taken over by malevolent hackers and are known as zombies or bots. By locating weak points that they may infect with malware through phishing assaults, malvertising attacks, and other ways for mass infection, the attackers will harvest these systems. 

 

The hijacked computers might be anything from common home or office PCs to DDoS devices—the Mirai botnet is infamous for assembling an army of hacked CCTV cameras—and it's quite likely that their owners are unaware of the situation because they continue to operate normally in most ways.

 

The infected computers are waiting for a remote command from a so-called command-and-control server, which acts as the attack's command hub and is frequently a hacker-infested computer. When released, all of the bots make an effort to use a resource or service that the victim makes online. 

 

Each bot would have sent harmless and typical queries and network traffic to the victim individually. However, because there are so many of them, the requests frequently exceed the capabilities of the target system, and because the bots are typically just regular computers that are dispersed throughout the internet, it can be challenging or impossible to block their traffic without also disconnecting reputable users.

 

DDoS assaults fall into one of three categories, which are primarily defined by the sort of traffic they direct at their targets' systems:

 

1. Protocol or network-layer DDoS attacks: 

 

Large amounts of packets are sent to targeted network infrastructures and infrastructure management tools during protocol- or network-layer DDoS attacks. These protocol attacks, which are measured in packets per second, include SYN floods and Smurf DDoS, among others (PPS). 

 

Layer 3-4 attacks on your network, also known as network layer attacks, are virtually invariably DDoS attacks designed to clog the "pipelines" linking your network. This category of attack methods includes NTP amplification, DNS amplification, NTP flood, SYN flood, and other types of attacks.

 

2. Application-layer attacks: 

 

Attacks at the application layer are carried out by bombarding targets with specially designed requests. Attacks at the application layer are quantified in terms of requests per second (RPS). 

 

Application layer assaults, also known as layer 7 attacks, are attempts to overwhelm a server by delivering a lot of requests that demand a lot of processing power. They can be DoS or DDoS threats. This group of attack methods includes HTTP floods, slow attacks (such as Slowloris or RUDY), and DNS query flood attacks, among others.

 

3. Volume-based attacks:

 

Volume-based attacks use a great deal of fake traffic to saturate a resource, like a server or a website. Attacks using faked packets, UDP, and ICMP are among them. A volume-based attack's size is expressed in bits per second (bps).

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How does a DDoS attack happen?

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Important techniques used in all types of DDoS attacks include:

 

• Reflection: 

 

The attacker may create a faked IP address that makes it appear as though the packet actually came from the target victim, transmit it to a third-party system, and have that system "reply" to the victim. This makes it even more difficult for the target to discern the true source of an attack.

 

• Spoofing: 

 

Attackers are said to be spoofing IP packets when they alter or obscure header information that should identify their source. The victim cannot stop assaults originating from the packet's genuine source because it cannot see it.

 

• Amplification: 

 

It is possible to deceive some online services into responding to packets with several or very big packets.

 

An increasingly popular DDoS attack known as a reflection/amplification DDoS can be created by combining all three of these methods.

 

Also Read | Ways to Avoid Phishing

 

                             

DoS vs. DDoS:

 

Regular and distributed denial of service attacks differs significantly from one another. A DoS attack employs a single Internet connection to overwhelm a target with bogus requests or exploit a software weakness, usually in an effort to deplete server resources (e.g., RAM and CPU).

 

DDoS attacks, on the other hand, are launched from numerous linked devices that are dispersed around the Internet. The sheer number of devices involved makes these multi-person, multi-device barrages often difficult to evade. DDoS attacks typically aim at the network infrastructure in an effort to saturate it with extremely high levels of traffic, unlike single-source DoS assaults.

 

DDoS attacks vary in terms of how they are carried out as well. Denial of service attacks is typically launched using custom scripts or DoS tools (such as the Low Orbit Ion Canon), whereas DDoS attacks are launched from botnets, which are sizable groups of connected devices (such as smartphones, PCs, or routers) that have been infected with malware that enables remote attacker control.

 

Also Read | Top 10 Anti-Phishing Tools in the Market

 

How to recognize a DDoS assault?

 

An abrupt slowdown or unavailability of a website or service is the most evident sign of a DDoS assault. However, since numerous factors, including a real increase in traffic, might result in performance concerns, more research is typically needed. You can identify some of these obvious indications of a DDoS assault using traffic analytics tools:

 

• Suspicious volumes of traffic come from a single IP address or a group of IP addresses.

• A deluge of traffic from users who have the same device, location, or web browser version or who otherwise have a similar set of behaviors.

• Unexpectedly high demand for a single page or endpoint.

• Strange traffic patterns, such as peaks at strange times of day or patterns that don't seem to be natural (e.g. a spike every 10 minutes).

 

Depending on the type of assault, there are other, more precise indications of DDoS attacks.

 

Also Read | What is a Man-in-the-Middle Attack?

 

How to counter a DDoS assault?

 

Because a DDoS assault mimics the web traffic that your actual clients utilize, as was already mentioned, mitigation is challenging. By simply blocking all HTTP requests, you may "halt" a DDoS attack on your website. In fact, doing so could be critical to preventing your server from crashing. But by doing that, you also prevent anyone else from accessing your website, which proves that your attackers were successful in their objectives.

 

You can lessen the attack while keeping your services at least partially operational if you can distinguish between DDoS traffic and legitimate traffic as described in the previous section. 

 

For example, if you know the attack traffic is coming from Eastern European sources, you can block IP addresses from that region. Shutting down any publicly exposed services that you aren't using is an excellent precautionary measure. You can disable services that could be subject to application-layer assaults without having any impact on your ability to provide web pages.

 

However, in most cases, simply being able to handle a lot of incoming traffic is the strongest defense against DDoS attacks. Depending on the circumstances, that could entail either strengthening your own network or using a content delivery network (CDN), a service built to handle high volumes of traffic. You might be able to employ the mitigation services offered by your network service provider.

 

Also Read | Cyber Security Awareness: Ways to Protect Cyber Attack Vulnerability

 

 

DDoS Challenges:

 

• DDoS assaults can be conducted in a number of ways, including DNS flooding, saturating available bandwidth, and abusing cloud resources.

• Hackers are increasingly conducting lower-intensity "degradation of service" assaults using techniques comparable to DDoS that cause expensive service slowdowns without completely shutting down resources. These attacks can occasionally go unnoticed for a long time by DDoS defense systems.

• The number of network entryways from which companies might be attacked is mushrooming due to the development of IoT devices.

• Endpoint monitoring technologies are becoming increasingly necessary to swiftly and efficiently stop floods at both the network and application tiers.

• The victims of DDoS attacks are repeatedly targeted in 87% of cases. When a company is found to be vulnerable, hackers keep attacking.

 

Also Read | Proxy Firewall: An Enhanced Level of Security

 

 

Summary:

 

DDoS assaults are growing more frequent and have the potential to harm systems for billions of dollars.

 

As you have no control over the traffic to your site, it is impossible to completely protect against DDoS attacks. But if you make use of one of the aforementioned services, stay away from inexpensive hosting, and get ready for a DDoS attack when it does happen, you will be much less likely to experience harm.