Published: 14/04/2020

Application DDoS Attack

An Application DDoS attack is designed to carry out a large amount of activity so that the server under attack is unable to provide the service that it is in place to provide. While this is partly done by the quantity of traffic, it is also done by formatting the network requests in such a manner as to exploit weaknesses in the network protocols that make failure more likely.

How an application DDoS attack works

An Application DDoS attack comes in many forms, but they all accomplish the same goal. The attacker creates a large number of requests for data or other processes which are designed to be inefficient on the target application server so that it becomes overwhelmed and unable to service normal traffic.

Many times this is aimed at websites through image downloads and script calls, creating bandwidth usage spikes that move faster than the servers can process them. In some cases it will also cause web pages to load slowly or not at all, denying visitors access to important information. This type of attack can work against any website hosted over HTTP or HTTPS including online banking sites, government agencies and commercial web services.

The reason why these attacks are called “Application” DDoS attacks is because it is carried out by attacking the application layer of the TCP/IP model. This interface is responsible for all communication between web servers and browsers, so it also integrates how a website looks from its visitors’ point of view. When an Application DDoS attack takes place, it can cause the sites to load slowly or become inaccessible in some cases.

Since these types of attacks have been around since about 2005, most modern websites have defenses against them that normally keep attempts at these kinds of attacks from taking down their servers on a regular basis. These site owners regularly monitor traffic levels for spikes that would indicate a potential DDoS attack in order to take steps to counter it before any damage occurs. Since most attacks tend to happen during peak times, like early in the week or on weekends when more people are online, it is also a good idea to prepare for them by boosting server capacity during these attack windows.

That being said though, even some of the most well-prepared servers have been taken down in Application DDoS attacks since they tend to be very large. These types of attacks can sometimes exceed 100 Gigabits per second and take down sites that are protected with no more than basic web firewalls designed to stop smaller botnets and script kiddies from causing problems.

Application DDos Attacks can come from several places:

  • Flood networks
  • Malware code injection
  • Compromised systems.

A common form of the latter attacks is using botnets. Botnets are virtual armies of hacked systems that can be controlled by a single individual to carry out all kinds of ill-intended actions, Application DDoS being one of them.

Types of application DDoS attacks

There are three main types of Application DDoS Attacks:

  • Volumetric attacks – Volumetric attacks carry out a basic form of DDoS by creating large numbers of TCP connections with the target server. While this type of attack is known as a volumetric attack, it can also be described as a flood or brute force attack depending on the size and power of the attacker’s network in comparison to the victim’s. These attacks rely on volume to overwhelm their targets and are not always effective.
  • State exhaustion attacks – These more advanced forms of Application DDoS attacks work by forcing servers into states where they cannot properly process any incoming requests whatsoever. This can include SYN scanning, resource exhaustion and memory consumption among others. The goal is to crash the server, causing it to crash by overloading the CPU or other resources. As with all DDoS attacks, there is a specific goal to these kinds of assaults in mind beyond taking down the victim site as fast as possible.
  • Volatile application-level attacks – These kinds of Application DDoS Attacks are the most dangerous ones that take advantage of weaknesses in protocols like HTTP and DNS. These attacks use malformed traffic like long requests lines or large code payloads to overwhelm servers and cause an outage. This type of attack has been one of the more destructive methods used by “hacktivists” since they can work well against targets who have not invested much into resilience during their deployment window.

How to detect an application DDoS attack

Detecting an Application DDoS Attack is not always easy. It requires a combination of skill, experience and know-how to monitor for signs that your system may be under attack.

The best time to detect threats like application layer DDoS attacks is before they happen, so there are three main steps you will want to take in order to foresee and help prevent these types of attacks:

  • Monitoring – Monitoring your web traffic levels can alert you when something abnormal happens with the amount of traffic hitting your network. Most networks have ways of checking for things like this by setting up alerts or placing monitoring on specific resources such as bandwidth consumption or CPU load levels. This can help you identify problems that arise during peak times more quickly enabling you to mitigate them much easier if they are in fact Application DDoS Attacks. Monitoring will not, however, alert you to the content of the traffic. Setting up a Network Intrusion Detection System (NIDS) can help with this next step.
  • Signature scanning – Using an NIDS to scan for signature-based events is a good way to determine what type of malware may be causing the problem on your end. Since practically every network attack that takes place leaves behind a fingerprint or signature of some kind, NIDS systems can use these markers to differentiate between common attacks and anomalies that need further analysis from a security standpoint. In Application DDoS Attack cases though, the biggest challenge isn’t just finding out that an attack is taking place but also figuring out how to stop it before the server goes down.
  • Vulnerability patching – Patching servers and applications is the only way to prevent them from becoming a major vulnerability in your program or network’s infrastructure. Most of these attacks exploit vulnerabilities that are known, so keeping systems up to date on their latest patches can prevent many types of Application DDoS Attacks.

By following these three steps, you will have a much easier time detecting and stopping application layer DDoS attacks before they cause too much damage.

How to prevent an application DDoS attack

Preventing or stopping an application layer denial-of-service attack is more difficult than detecting one since every attack takes place differently with enough variations that there may be no way to predict what will happen when they strike your network. However, knowing some general steps you can take will help give you options for dealing with these types of threats.

  • First and foremost, make sure that you have a solid backup plan in place. If your site is taken down due to an Application DDoS Attack, being able to recover quickly will be paramount since many attackers try to exploit vulnerability windows where sites are offline for extended periods so they can take over the domain name or similar key resources. This means having plans in place like a manual fallback procedure for critical services in case there is no automatic way to get back online when you are under attack.
  • Secondly, make sure that your core protocols are strong enough to prevent exploitation from taking place if at all possible. Improving the security of your underlying network infrastructure by keeping it up-to-date and protected will help mitigate any issues that the bandwidth of Application DDoS Attacks can cause.
  • Thirdly, make sure your systems are geared towards being able to handle high traffic levels by either upgrading or adding in additional resources to provide a higher level of processing where necessary. This is especially important for servers that may be targeted more often due to your business model, products and services offered or any other reason. Even if you take all these steps though, application layer DDoS attacks will likely become more frequent as time goes on so being prepared is key for minimizing the damage they can cause in today’s online world.

The more an attacker knows about your server and network architecture, the easier time they can have taking it down. They can also use social engineering to try and get you to do things that compromise your security or cause you to take other actions that hurt your chances of surviving Application DDoS attacks.

By following the steps above, you will be much better prepared for dealing with this type of threat.

How to recover from an application DDoS attack

While there is no guaranteed way to survive an Application DDoS Attack, taking steps like those listed above will give you the best chance of coming out okay in the end. That said, it’s also important to know what actions to take after an attack has taken place so your site can come back online quickly and resume normal service levels without any problems.

  • First and foremost, make sure that all redundant systems are still online and functioning properly. While it may be tempting to disable some of them or even shut down entire systems as a precautionary measure after a major outage, doing so could cause more harm than good if your system starts having issues rebooting into critical subsystems. Instead, get all non-essential services restored first before on-lining anything else.
  • Second, make sure that any backup systems are restored so you have an up-to-date copy of your site to work with. While it’s not a good idea to move servers around in the same network segment or server closet after an incident like this due to security reasons, investing in dual power supplies and/or generators to provide enough power for a clean restart may be necessary.
  • Lastly, double-check all software dependencies by performing some basic testing on the new configuration before putting everything back online just in case something was missed during the restoration process. This will help ensure that there are no subtle issues remaining from the attack that could cause problems down the road. Once everything is working as expected and you’re ready for service again, notify everyone involved in the restoration process that everything is back online and to not touch anything else unless explicitly instructed by one of the system administrators.

The more you know about what happened during an Application DDoS Attack, how it affected your site and what steps were taken by yourself and others involved in defending against or recovering from the incident, the better off you will be during any similar situation down the road within your business lifetime.

Frequently asked questions about application DDoS attack

What are some of the costs associated with a successful application DDoS attack on your company or business?

While there is no specific list of costs that you can expect to be associated with an Application DDoS Attack, the potential damages could range from a few thousand dollars all the way up to tens of thousands.

How do you know if you’re under attack?

In most cases, an Application DDoS Attack is obvious and easy to spot as the network traffic volumes are much higher than usual. This can sometimes be more difficult for smaller networks where you may only get one report from a customer that something doesn’t look right from across the internet. If you have monitoring in place though, these types of issues should hopefully be caught before they become too serious so act on them quickly if it turns out to be a major incident like this.

What can I do to prepare my business or company for an application DDoS attack?

According to some experts who study this type of threat, one of the best things you can do is try and recreate the conditions under which an attack might take place so that it’s easier and faster to detect when one is underway.

Where do application DDoS attacks come from?

Application DDoS Attacks can come from anywhere on the internet using any protocols that are supported by your network infrastructure. As a result, they can be very difficult to track down and stop so it’s important to have monitoring software in place at all points of entry for traffic as well as a good procedure for reacting quickly when an attack strikes before too much damage is done.

When should I expect an application DDoS attack according to statistics?

According to some researchers, there are certain times of day where you can see increased reports about this type of event taking place more than others. For example, during the afternoons in North America or between 2PM – 3PM around the world. It’s not clear why this happens, but it might have to do with how people are more active on their computers during those times so they’re less likely to notice a problem and report it at other hours.

What are some common signs of application DDoS attacks?

If you notice high volumes of network traffic coming from a location on the internet that does not normally generate much, this could be an early sign of a potential Application DDoS Attack. Watching for unexpected connections to ports that aren’t part of your regular services can also be helpful so look out for new or unusual behavior like these when monitoring your networks to see if there are any problems.

Do these types of attacks only affect large companies or can they also affect small businesses as well?

Application DDoS Attacks can and do affect all types of organizations. According to some sources, even providers for smaller services in the cloud have been affected by this type of threat before so it pays to be aware of what’s out there and what you can do about it.

What are some measures that I can take now to prevent application DDoS attacks from affecting my business?

There are a number of things you can consider here including deploying monitoring software tools on all points of your internet-facing network as well as making sure that those tools report immediately back to you whenever they notice unusual activity. It also helps a lot if you have an incident response plan in place for handling these attacks when they do happen before they strike as effectively and quickly as possible.

What are some common causes behind application DDoS attacks?

Threats like Application DDoS Attacks can come from anywhere and for a large number of different reasons so identifying every cause is not possible here. That said, make sure that you take proper care in securing your website at all times online by implementing reasonable policies and procedures as well as keeping up-to-date with security software that mitigates both known and unknown threats at this time.

How do application DDoS attacks and other DDoS attacks differ?

Unlike traditional DDoS Attacks that typically degrade the performance of computer networks by overloading them with traffic in order to overload network services, Application DDoS Attacks are designed specifically to bring down websites and services by exploiting the weaknesses in their code structure. As a result, they can be much more difficult to stop than other types of threats like this so it pays to have good prevention measures in place for both when you first deploy your systems online and also going forward.

Is there any way I can protect my customers from being impacted by an application DDoS attack?

The best way to do this is by having a hosting provider or business partner who has proven experience with defending against these types of threats before and regularly keeps in touch with security researchers about the latest trends and developments relating to this subject. That way, they can keep their networks current and prevent any potential problems before they start.

Why are application DDoS attacks on the rise?

There are a number of reasons for this including:

The rise in mobile devices that access the internet from anywhere – This makes it simple for anyone to launch an attack against your site from almost any location on the planet so take special care over how you secure everything online today.

The use of scripts and bots by attackers – Applications like these can be used by cybercriminals to execute DDoS attacks with greater precision than ever before. Make sure you understand exactly what you’re up against at all times so you can prevent a problem before it starts, if possible.

What else should I know about application DDoS attacks?

Depending on your particular network setup, you may also be vulnerable to spoofing attacks which can be used in an attempt to make your users access fake websites or enter sensitive data into incorrect fields when filling out forms. These types of things can have serious impacts as well so take steps to help prevent them from happening if possible.

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