Layer 7, commonly known as the “application layer,” is the top of the internet’s seven-layer Open Systems Interconnection (OSI) model. Layer 7 attacks, or application layer attacks, are interchangeable terms used to describe distributed denial of service (DDoS) attacks at this level.
According to NETSCOUT’s Threat Intelligence Report, over 6 million DDoS assaults were launched in the first half of 2022. This is a 2% decrease from the second half of 2021. DDoS attacks are advanced and can happen at any layer of the OSI model. However, they occur most commonly at layers 3, 4, and 7.
DDoS attacks at the 7th layer aim to flood servers or networks with traffic (usually HTTP traffic). For example, attacks may include overloading and stalling a server by sending tens of thousands of requests for a certain webpage per second or repeatedly calling an API until the service fails.
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Layer 7 DDoS attacks are much more complicated than other DDoS operations. Therefore, they require added levels of precautionary measures to avoid these attacks.
In this article, we’ll look at the toughest layer 7 attacks and tell you how to prevent them.
The Toughest Layer 7 Attacks and How To Prevent Them
Layer 7 attacks are DDoS attacks that take place discreetly, efficiently, and repeatedly. Layer 7, or the application layer, determines how data is shared with the end user. The majority of cyberattacks leverage loopholes or vulnerabilities in any of the seven layers, but DDoS attacks primarily target the application layer.
These attacks can be broadly grouped into three categories:
1. Application Layer Attacks
Typically, these attacks operate by overloading the server through numerous resource-intensive requests. Their primary target is specific services on web pages or applications that have database or file access.
Application layer attacks become extremely difficult to distinguish because they appear as legitimate traffic.
HTTP flooding is one of the most notorious examples of DDoS attacks. It is equivalent to refreshing a web page several times. These floods are complex and sophisticated enough to execute from IP addresses with different user agents and referrers.
2. Protocol Attacks
Protocol attacks are more commonly known as state-exhaustion attacks. These attacks disrupt the services of a website by throwing large data packets to a system’s routers and firewalls.
The data is structured, disjointed, transported, and reunited at the destination in transport layers. This attack attempts to clog up these pipelines. Conventionally, for a TCP connection, a three-layer handshake is established to complete the connection.
A SYN flood, or TCP connection, attack compels the bots not to respond after the initiation of a handshake. This leaves the server hanging, blocking an open port and waiting. When this is done on a large scale, it blocks all the ports and ultimately forces the server to shut down.
3. Volume-Based Attacks
Volume-based attacks, as their name indicates, aim to consume all available bandwidth between a system and the wider internet.
These attacks entail sending several requests for enormous volumes of data using the target’s IP address. Unlike other forms of cyberattacks that leverage or exploit the system’s services, most traffic involved in a volume-based DDoS attack is fake.
To overwhelm the network, attackers employ:
- Spoofing: With spoofing, the attacker alters the header data that identifies the source of the request.
- Amplification: The amplification approach involves the attacker sending a single fake request to third-party services.
- Reflection: Attackers employ the reflection method when they wish to hide their involvement. They use bots to achieve this.
The Best Practices for Layer 7 Attack Prevention
Cyberattacks can happen to anyone at any time. Healthcare data breach statistics show how damaging these attacks can be, with millions of illegally accessed patient records and millions of dollars spent to recover.
Thus, taking the right steps to prevent attacks is crucial. Let’s look at the best ways you can protect yourself.
1. Optimally configure your network devices
A strong firewall system can make all the difference when defending against attacks. Firewalls control incoming and outgoing traffic, which is essential in blocking malicious attacks.
A few key steps to consider when optimizing your firewall are as follows:
- Block all traffic to your network and control who has access.
- Change the filtering rules to move unwanted inbound traffic to the router.
- Clean up your rule base by removing unused rules and simplifying them as needed.
- Always ensure your software is updated to the newest version.
- Utilize several firewalls to boost your protection.
Firewall management is a great way to help optimize and configure your security system. Organizations should utilize firewall systems to easily control access, block malicious traffic, and secure data.
2. Closely manage all security updates
DDoS attackers search for weaknesses in the system. A DDoS teardrop attack, for instance, inhibits the network layer from breaking apart and reassembling data packets, resulting in jams. It exploits a flaw that the most recent Windows operating systems have addressed.
This is why it is crucial to ensure your system is updated, as out-of-date versions leave it exposed.
Service providers identify and disclose new vulnerabilities regularly. Social media, notably Twitter, offers an effective way to discover new vulnerabilities.
There are also free vulnerability scanners available online.
3. Utilize multiple servers
Utilizing multiple servers makes the hacker’s job more complicated. If a hacker targets one server, the rest can continue running. You can host these servers in different countries to add an extra layer of protection.
You can also consider using a content delivery network (CDN). CDNs divide the load equally across several dispersed servers since DDoS assaults function by overwhelming a server.
4. Put a cap on network broadcasting
When you have multiple devices connected to the same network, hackers can facilitate access to them all. The more devices connected to your network, the bigger the DDoS impact. You can prevent this by restricting network broadcasting between devices.
The Importance of Using an Anti-DDoS Service
As cyberattacks continue to become more sophisticated, so are the responses to malicious activities on large-scale networks and internet-facing services. While important, traditional cybersecurity defenses are not always enough to ensure continuous uptime and system availability. For this reason, additional security measures, such as anti-DDoS services, were developed.
An anti-DDoS service helps identify and filter out malicious traffic in real time. It allows legitimate traffic to reach the target system and prevents service disruption. This also boosts performance, as less unwanted traffic frees up resources.
Companies and organizations can protect themselves from layer 7 attacks by utilizing an anti-DDoS service. As part of an online defense strategy, DDoS protection services can help prevent incoming attacks from reaching target networks and systems.
Many anti-DDoS services are available, such as cloud-based, on-premise, and hybrid solutions.
- Cloud-Based: Third-party providers give their customers cloud-based anti-DDoS services that mitigate attacks and minimize impact without investing in hardware or software, reducing overall costs.
- On-Premise: This service type requires organizations to install and manage their hardware and software.
- Hybrid: These solutions combine the advantages of cloud-based and on-premise solutions.
DDoS protection services are a great tool to avoid attacks and increase online safety. They help ensure that online services are not disrupted, making them more reliable and increasing availability.
Conclusion
Layer 7 attacks, such as DDoS threats, are not only growing more harmful, but they are also happening more frequently. By 2023, experts estimate that there will be 15.4 million DDoS attacks annually.
This statistic suggests that almost every company will experience a DDoS attack at some point. Thus, preparing in advance with the above-mentioned precautionary measures will help keep you one step ahead of potential attacks.
FAQs
What is layer 7?
Layer 7 is the top layer of the internet’s seven-layer Open Systems Interconnection (OSI) model. It’s known as the “application layer.”
What are layer 7 attacks?
Layer 7 attacks are distributed denial of service (DDoS) attacks at the OSI model’s application layer. The purpose is to overload or disrupt servers by flooding them with HTTP traffic and various protocols.
How are layer 7 attacks different from other DDoS attacks?
Layer 7 DDoS attacks are much more complicated than other DDoS operations because they occur quietly, constantly, and efficiently. They also usually appear as legitimate traffic, making it hard to distinguish between legitimate traffic and an attack.
What are the three categories of layer 7 attacks?
There are three categories of layer 7 attacks—application layer, protocol, and volume-based attacks.
- Application layer attacks overload the server via multitudes of resource-intensive requests.
- Protocol attacks disrupt services by pumping large data packets to a system’s network infrastructure, such as routers and firewalls.
- Volume-based attacks aim to deplete all available bandwidth between a networked system and the internet, taking that system offline.
How should an organization protect itself from layer 7 attacks?
There are many best practices for preventing layer 7 attacks. These include optimizing network devices, monitoring, controlling, and implementing all security updates, having server redundancy, and using anti-DDoS services.
