DDoS attacks, among other cybersecurity and cloud security vulnerabilities, have increased in size, scope, and frequency in recent years. According to a Kaspersky Lab survey, DDoS attacks increased by 80% in the first quarter of 2020 relative to the same quarter of 2019.
According to research, the typical DDoS attack in 2021 will use more than 1 Gbps of data, which is more than enough to bring most small-to-medium-sized websites to a halt. In addition, the total time of an attack has increased significantly, with most attacks currently lasting 30 minutes to an hour rather than the ten minutes or fewer seen in previous years. Read on to learn more about distributed denial-of-service attacks and how your organization can help prevent them.
Why Are DDoS Attacks so Harmful?
DDoS attacks can overrun and overwhelm data centers, driving up costs for service providers. A Dos attack, such as a flood attack, can cause lengthy downtime and connectivity issues for users. A successful DDoS attack can bring down network infrastructure in real-time, causing network security issues. Your incident response team should be equipped to deal with DoS, DDoS, and other serious cyber attacks.
What Is a DDOS Attack?
DDoS (Distributed Denial of Service) is an assault on a server initiated from several channels with the aim of rendering a computer’s bandwidth or facilities inaccessible. DDoS attacks are cyberattacks that strike vital infrastructure in order to interrupt network service or communication, causing users of the targeted resource to experience a denial of service. A DDoS attack targets a single device by combining the computing capacity of several malware-infected machines.
One of the most dangerous attack vectors in a hacker’s arsenal is the DDoS attack. Denial-of-service attacks can strike at any moment, affecting any aspect of a website’s operations or infrastructure, and resulting in major service disruptions and financial losses. DDoS attacks used to be a source of entertainment for some hackers, but evidence reveals that they’re increasingly being used by cybercriminals to make money or to cause havoc for political reasons.
How To Identify a DDoS Attack
A site or application unexpectedly being sluggish or inaccessible is the most apparent symptom of a DDoS attack. However, since a variety of other factors such as a genuine traffic surge may trigger related performance problems, further analysis is normally needed. The following signs of a DDoS attack can be detected using traffic analytics tools:
- Unusual levels of traffic coming from a single IP address or a number of IP addresses.
- A surge in traffic from users with a common behavioral profile, such as system model, geolocation, or web browser version.
- Unexpectedly high demand for a single page or endpoint.
- Unusual traffic trends, such as surges at unusual times of day or patterns that seem to be unnatural (e.g. a spike every 5 minutes)
Types of DDoS Attacks & How Each Work
Various forms of DDoS attacks exploit different aspects of a network link. To understand how various DDoS attacks operate, you must first understand how a network link is established.
On the Internet, a network is made up of several different components or “layers.” Each layer in the model serves a different purpose, similar to how each layer in a house serves a different purpose.
The OSI model (shown below) is a seven-layer analytical structure for describing network communication.
How do you prevent a DDOS Attack?
You can help avoid a distributed denial-of-service attack by doing the following:
- Creating a strategy for dealing with denials of service.
- Securing the resources of the network.
- Filtering firewalls and routers at the network’s edge to detect and block DDoS links.
- Blackholing the DDoS-attacked site, routing all traffic to an invalid IP address.
Types of DDoS Attacks
Application Layer Attacks
An application-layer attack targets the 7th layer that generates web pages on the server and delivers them in response to HTTP requests. On the client-side, a single HTTP request is computationally inexpensive, but it can be costly for the target server to react to since the server must often load several files and perform database requests in order to generate a web page.
Layer 7 attacks are difficult to protect against since distinguishing malicious traffic from legitimate traffic can be difficult. The aim of a layer 7 DDoS attack is to consume the target’s resources in order to cause a denial-of-service attack.
The OSI network model’s application layer is the topmost layer and the one nearest to the user’s interface with the device. The application layer attacks are mainly focused on direct web traffic. HTTP, HTTPS, DNS, and SMTP are also possibilities.
Application-layer attacks are more difficult to detect because they usually include a limited number of devices, often only one. As a result, the server may be duped into accepting the attack as yet another burst of legitimate traffic.
HTTP Flood Attacks
This assault is analogous to repeatedly refreshing a web page on several devices at the same time – a huge amount of HTTP requests overwhelm the site, causing a denial-of-service. This is a form of attack that can be straightforward or complex.
Simpler implementations can use the same set of attacking IP addresses, referrers, and user agents to access the same URL. Complex versions can employ a large number of attacking IP addresses and use random referrers and user agents to target random URLs.
Protocol attacks, also known as state-exhaustion attacks, interrupt operation by using too many server resources and/or network equipment resources such as firewalls and load balancers. Protocol attacks take advantage of flaws in the protocol stack’s layer 3 and layer 4 to make the target unavailable. A protocol attack targets link tables in network areas that deal with connection verification directly. The assaulting machine will cause memory buffers in the target to overwhelm and potentially crash the device by sending a series of sluggish pings, intentionally malformed pings, and partial packets. Firewalls may also be targeted by a protocol attack. This is why a firewall by itself would not be sufficient to prevent denial of service attacks.
Hackers exploit the TCP handshake with an “Initial Connection Request” which are SYN packets with spoofed source IP addresses to a destination — the sequence of communications by which two computers initiate a network connection. The target machine responds to each communication request and then waits for the handshake’s final move, which never happens, wasting the target’s resources in the meantime.
The SYN flood, which uses the three-way handshake method to create a TCP/IP connection, is one of the most frequent protocol attacks. Before forming a link, the client usually sends a SYN (synchronize) packet, receives a SYN-ACK (synchronize-acknowledge), and responds with an ACK. The client only sends SYN packets during an attack, causing the server to send a SYN-ACK and wait for the final phase, which never comes. As a result, network services become congested.
Would-be hackers often mix these three tactics to strike a goal from many sides, totally crippling the protections before stronger and more comprehensive countermeasures can be implemented.
A volumetric attack tries to create a gridlock of the internet traffic using all the available bandwidth between the victim and the rest of the web. Amplification or another method of gathering large amounts of traffic, such as botnet requests, are used to distribute terabytes worth of data to a destination.
The most popular DDoS attack causes a machine’s network bandwidth to be overburdened by overwhelming it with fake data requests on any open port it has. Since the bot fills ports with data, the system is constantly searching for malicious data requests, leaving no space for legitimate traffic to pass through. The two most common types of volumetric attacks are UDP floods and ICMP floods.
User Datagram Protocol (UDP) refers to the basic transfer of data without verifying its integrity. Unfortunately, the UDP format lends itself well to rapid data transfer, making it a prime weapon for attackers.
The Internet Control Message Protocol (ICMP) is a protocol that allows network computers to connect with one another. An ICMP-focused attack involves targeting nodes that send false error requests to the target. Similar to how a UDP attack operates, the aim must comply with these demands and is unable to respond to legitimate ones.
Amplification attacks take advantage of a bandwidth gap between the attacker and the web resource being attacked. The resulting amount of traffic will interrupt network capacity as the cost difference is magnified over multiple requests. The malicious user will get more out of less by sending small queries that result in large responses. The target IP address receives a response from an open DNS server after sending a request with a spoofed IP address (the victim’s IP address).
Differentiating between attacks and regular traffic is a major problem when dealing with a DDoS attack. For example, if a company’s website is flooded with excited buyers as a result of a new launch, cutting off all visitors is a mistake. If the corporation unexpectedly receives a flood of traffic from established attackers, mitigation attempts are almost certainly needed.
The challenge is distinguishing genuine consumers from attack traffic. DDoS traffic can take many forms on the digital Internet. From unspoofable single source attacks to dynamic and flexible multi-vector attacks, the traffic can be designed in a variety of ways. A multi-vector DDoS attack employs multiple attack vectors to overpower a target in a variety of ways, potentially diverting mitigation efforts away from any one direction.
Multi-vector DDoS attacks several layers of the protocol stack at the same time, such as DNS amplification (layers 3/4) combined with an HTTP flood (layer 7), for example. In order to address various trajectories, mitigating a multi-vector DDoS attack necessitates a range of techniques.
In general, the more subtle the threat, the more complicated it would be to distinguish attack traffic from usual traffic – the attacker’s target is to fit in as far as possible, making prevention attempts as ineffective as possible.
Mitigation efforts that indiscriminately lower or restrict traffic risk mixing together good and bad traffic, and the attack can adjust to avoid countermeasures. A layered approach can have the most benefit in overcoming a dynamic effort at disruption.
Develop a DDoS Attack Prevention Response Plan
Centered on a comprehensive security review, create a DDoS preventive strategy. Larger businesses, unlike smaller businesses, can entail complex infrastructure and the participation of several teams in DDoS preparation.
When a DDoS attack occurs, there is little time to consider the right course of action. They must be described ahead of time in order to allow for quick responses and prevent any negative consequences.
The first step toward a robust defensive policy is to develop an emergency management plan. A DDoS response plan can become very extensive depending on the infrastructure. When a malware attack occurs, the first action you take will determine if the attack will stop. Make sure the data center is ready and that everyone on the staff understands their roles. You’ll be able to reduce the burden on your company and save yourself months of healing time this way.
Any company’s main components are the same, and they are as follows:
Make a comprehensive list of the assets you’ll need to deploy sophisticated threat detection, evaluation, and filtering tools, as well as security-enhanced hardware and device defense. Assemble a response group. Define main team members’ duties to ensure a coordinated response to the attack as it occurs.
Define the protocols for warning and escalation. Make sure everyone on the staff knows who to call in the event of an attack.
Include a list of internal and external contacts that need to be notified of the attack. Establish connectivity techniques for the clients, cloud storage provider, and any security vendors, as well.
Protect the Infrastructure of Your Network
Only with multi-level defense mechanisms in place will network security risks be mitigated.
Advanced intrusion detection and vulnerability control systems, for example, incorporate firewalls, VPNs, anti-spam, content filtering, load balancing, and other DDoS security layers. They work together to provide continuous and reliable network security, preventing DDoS attacks. This covers everything from detecting potential traffic inconsistencies to stopping the attack with the utmost precision.
Since most mainstream network equipment only has minimal DDoS mitigation capabilities, you may want to outsource any of the extra services. You will use innovative prevention and security resources on a pay-per-use basis through cloud-based solutions. This is a fantastic choice for small to medium-sized firms looking to keep their defense budgets under control.
Additionally, you can ensure that the systems are up to date. The programs that are out of date are normally the ones with the most flaws. Denial of Service (DoS) attackers look for flaws. You will shut further doors to attackers by patching the infrastructure and downloading new software versions on a daily basis.
A Web Application Firewall (WAF) is a mechanism that can help prevent DDoS attacks at layer 7. When a WAF is placed between the Internet and an origin site, it may act as a reverse proxy, shielding the intended server from malicious traffic.
Layer 7 attacks can be thwarted by filtering requests based on a set of rules used to classify DDoS resources. One of the most important features of a good WAF is the ability to easily apply custom rules in the event of an attack. More from Cloudflare’s Web Application Firewall (WAF).
Be on the Lookout for DoS Attacks
DDoS attacks are painfully common, and they are no longer exclusive to large companies. Small and medium-sized businesses are being increasingly targeted. This trend has increased the demand for multi-layered security technologies that can cover sensitive workloads completely.
Are you about to take the next step to guarantee the company’s survival? Contact our Touchstone Security experts to learn more about how to prevent the next DDoS attack from affecting your business.