Radar has landed - discover the latest DDoS attack trends. Get ahead, stay protected.Get the report
Under attack?

Products

Solutions

Resources

Partners

Why Gcore

  1. Home
  2. Developers
  3. What Is a Denial of Service Attack (DoS)?

What Is a Denial of Service Attack (DoS)?

  • By Gcore
  • June 8, 2023
  • 9 min read
What Is a Denial of Service Attack (DoS)?

The world of cybersecurity is ever-evolving, with new threats appearing almost every day. Denial of service (DoS) attacks are not new, but they can have a serious impact on a wide variety of services. Estimates suggest there are thousands of DoS attacks happening every single day and the numbers keep increasing. Their goal is to interrupt a device’s or service’s normal functioning.

When these attacks are successful, legitimate users won’t be able to access the service. Stopping such an attack once it happens is possible, but not always easy, which is why they can cost organizations a lot of time and money. Here’s everything you need to know about DoS attacks.

What Is a Denial of Service (DoS) Attack?

A denial of service (DoS) attack is a cyber attack that aims to make a device, service, network, or other information system unavailable to legitimate users. The hacker uses a single machine and typically floods the target with an extremely high number of requests. Eventually, the target machine can no longer process normal traffic.

When thinking of a cyber attack, for many people what comes to mind is someone trying to access data illegally. A DoS attack is not necessarily about accessing or stealing someone else’s data. The goal, in most cases, is to block users from accessing a service. Revenge, competition, extortion, and even activism are some reasons people resort to DoS attacks.

Sometimes, denial of service attacks serve as a precursor to other, more severe attacks. Once a device or service becomes inactive, the attackers can infiltrate other areas of the system and attempt to install malware with the aim of conducting a bigger attack in the future.

How Do DoS Attacks Differ from Distributed Denial of Service (DDoS) Attacks?

A distributed denial of service (DDoS) attack is a type of DoS attack that uses several distributed machines to launch the attack instead of a single machine.

DoS attacks come from one IP and are relatively easy to counter. DDoS attacks come from multiple IPs, which makes them more difficult to stop.

When the attack comes from distributed sources, it can be much harder to differentiate malicious traffic from normal traffic. As a result, DDoS attacks are harder to detect before they cause real damage. With a DoS attack, only one machine needs to be detected and stopped.

Types of DoS Attacks

Denial of service attacks are usually divided into two categories:

  • Buffer overflows, which crash web-based services. This is the most common type of DoS attack. The hacker drives high traffic and data to a network point. To handle the traffic, the system will need to use all its resources and memory, eventually causing it to crash.
  • Flood attacks, which flood services and devices. These attacks are carried out by sending high volumes of data packets, connection requests, and other types of traffic to a network or system.

Both types come with several other subtypes.

Types of Buffer Overflow Attack

The most notable buffer overflow attacks include:

  • Stack overflow. Here, the attacker sends more information to a device, program, or network than it can handle. The program will respond by using an area of the memory called “the stack.” When the stack is full, information can overflow to other parts of the program until it crashes.
  • Unicode overflow. This type of attack is designed specifically for programs that process text. The program usually expects to receive ASCII. Instead, the attacker sends Unicode characters beyond the program’s capacity. ASCII comprises 128 characters, the numbers, and letters you use every day. Unicode contains a much larger set of characters and symbols, up to 221 (roughly 2,000,000,) which won’t be readable to a program that expects ASCII. The extra text can overflow in other parts of the memory, causing the program to crash.

Types of Flood Attack

Flood attacks also come in different forms, such as:

  • ICMP flood. In this attack, the hacker hits the targeted network with a flood of Internet Control Message Protocol (ICMP) packets. ICMP is a protocol normally used to send error messages over the internet. When a network is flooded with such packets, it can’t handle any more legitimate traffic and may crash.
  • SYN flood. Here, the attacker tries to overwhelm a network by flooding it with connection requests; namely SYN packets. Devices communicate over the internet through the TCP protocol. To start the communication, one device will send an SYN (synchronize) packet to the others. To respond, the other device sends an SYN-ACK (synchronize-acknowledge) packet. During an SYN Flood attack, the attacker sends many SYN packets but never responds to SYN-ACK packets. The network begins slowing down, is unable to handle legitimate traffic, and could eventually crash.

Denial of Service Attack Examples

Denial of service attacks have a long history. The first documented attack of this kind is the Robert Morris worm attack that took place in 1988. The worm installed itself on systems connected to the internet, triggering DoS attacks and buffer overflows. At the time, there weren’t many computers connected to the internet and most were used in academia and research. However, estimates suggest up to 10% of the computers in the US were affected. Since then, these attacks have evolved, but their goal has stayed the same: limiting users’ access to certain services or devices.

Among recent examples, the most significant one is an attack from 2019—the DoS ransomware attack that affected Baltimore. During the attack, many of the city’s critical systems were taken down, including email systems, bill payment services, and even the 911 emergency dispatch. Over 1,000 home sales had to be delayed as a result of the attack.

From DoS to DDoS Attacks

Today, DoS attacks are not that popular anymore. Because they come from a single IP, they are fairly easy to counter with modern technologies. They can still happen, but most companies are ready to stop them within minutes or even seconds.

DDoS attacks, on the other hand, are more prevalent and still pose a huge danger. As an example, we had a 650 Gbps attack on our infrastructure in January 2023. Cybercriminals tried to take down a service belonging to one of our clients. The incident lasted for fifteen minutes, after which the attack stopped because we prevented any losses for our client, meaning the attack was ineffective.

An older, infamous example is the attack against GitHub on February 28, 2018. The attack originated from tens of thousands of points and managed to take GitHub down for 10 minutes. Another major DDoS attack happened in June 2022 and targeted a Chinese telecommunications company. The attack lasted a total of four hours, during which time 25.3 billion requests were sent. The hackers used a botnet with 170,000 IPs and managed to compromise servers located in 180 countries.

Preventing DoS Attacks

As the saying goes, prevention is better than cure. It’s true for your health and certainly true when it comes to DoS attacks. Preventing an attack is almost always easier than trying to stop one that’s already in progress. Here are a few easy steps to reduce the likelihood of experiencing a denial of service attack.

1. Use a Firewall

A firewall may sound like a simple solution, but can be very effective. In fact, the simplicity of it means many people overlook this step. If you manage a large network with a large number of people connecting to it—such as a workplace—make sure that everyone understands the importance of using a firewall.

This tool may not be completely bulletproof, but it can help block out much of the unwanted traffic. It may also spot suspicious activity and unauthorized traffic sources, making a DoS attack less likely to be successful.

2. Limit Connections

Many DoS attacks come from perfectly harmless-looking sources. One way to counter this is by limiting the number of connections that can come from a single IP address in a given time period. This can help prevent flooding attacks from one IP address, though DDoS attacks could still be successful.

3. Consider Network Segmentation

Network segmentation—splitting large networks into smaller ones—helps reduce the impact of a denial of service attack. To achieve this, you can create several VLANs and firewalls that will help limit the spread of the attack.

DoS attacks can still happen, but they will only affect one segment. The other parts of the network will keep working, reducing the damage to your services and the users. Network segmentation could even allow you to end the attack sooner by limiting the attack’s potential spread.

4. Use Load Balancing

Load balancing is a similar concept to network segmentation. In this case, though, you’re distributing traffic across multiple servers. If one server is overloaded or becomes unresponsive, the load balancer will send the traffic to another server.

5. Use Intrusion Detection and Prevention Systems

Intrusion detection and prevention systems to analyze incoming traffic and look for suspicious patterns. They can also limit the number of connections within a time frame from a certain IP if they detect unusual traffic coming from that source. They can be useful in preventing various types of malicious attacks, including DoS and DDoS attacks.

6. The Power of Education

When users are aware of potential DoS attacks, how they look, and when they can happen, prevention becomes easier. You can’t prevent something if you don’t know what it looks like or that it even exists!

Not every person has the knowledge to understand all the intricacies of DoS attacks, but by being aware of them and their potential risks, they can take simple, small steps to prevent them. For example, they can become more diligent with keeping their software updated, using strong passwords and changing them periodically, and using a firewall. Education is key to ensuring broad implementation of basic steps to prevent DoS attacks.

7. Conduct Periodic Penetration Tests

Penetration testing (pen testing) can help you spot vulnerabilities in your systems. These may not be visible “to the naked eye,” but you can be sure hackers will find them sooner or later, and use them against you.

Conducting periodic pen tests will help you stay one step ahead of attackers and address vulnerabilities before attackers can target them.

Mitigating DoS Attacks—What to Do if You’ve Already Been Hit?

Prevention is king, but sometimes hackers can exploit the smallest vulnerabilities, and attacks happen. It’s very difficult to stop a denial of service attack entirely. However, there are a few ways to mitigate and reduce their impact on your systems.

1. Traffic Filtering

Filtering can be effective both as prevention and mitigation. When you know you’re being flooded with unwanted traffic, filtering can be an effective solution to stop it in its tracks.

The filter will check all incoming traffic and make sure that only legitimate sources are allowed in. Sometimes it won’t stop the flood entirely, but it can reduce its load on your system, preventing it from becoming unavailable or crashing.

2. Scrubbing Services

Scrubbing services are like the cleaning crew that comes after the party. Their role is to check all existing traffic and remove malicious sources, while allowing legitimate traffic to continue.

Scrubbing centers are effective against all denial-of-service attacks—both DoS and DDoS. For example, scrubbing techniques stopped one of the most famous DDoS attacks of the past few years—the 2018 attack against GitHub. The traffic directed at GitHub was redirected to other data centers, where it was then “scrubbed.” As a result, only the legitimate traffic remained, and GitHub services were once again available.

3. Blackhole Routing

Blackhole routing means redirecting traffic to a null route, or a “black hole.” It is effective whenever a network is flooded with traffic from one or several IP addresses.

This technique has one major downside: it doesn’t always differentiate between malicious and legitimate traffic. In other words, you could be stopping access to your services for real users. It can still be a quick and effective way to mitigate a DoS attack in progress, though most agree it is not a great tool for prevention.

4. Encrypt Data and Use Backups

Encryption and backups will not stop a cyber attack in its tracks, but they are life savers if you do experience a DoS attack. They will reduce the risk of damage or theft, which can sometimes occur during or immediately after a DoS attack. Plus, if some of your systems do become unresponsive or corrupt, a backup will minimize your losses and will help you restore your workflow quickly.

How to Know if You’re Experiencing a DoS Attack?

Acting quickly is essential when you’re experiencing a DoS attack, but to do that, you must know what one looks like. The answer will vary slightly depending on your systems, any preventative measures you have in place, and the type of attack. But there are a few telltale signs that can help you recognize a denial of service attack.

1. Slow or Unresponsive Network

Before systems crash, they start slowing down for no apparent reason. You may notice that it’s taking longer to load websites, download files, or even send emails. If there’s no other reason for the slowdown, you may be experiencing a DoS attack.

2. Websites or Services Become Unavailable

Sometimes the network doesn’t crash all at once. You may have certain preventative measures like segmentation or load balancing that help reroute floods of traffic. Instead, you may notice that certain services become unavailable.

For example, your email could suddenly become unavailable. If you’re not having connectivity or other server issues, it is possible that your email server is being targeted by a DoS attack.

3. Unusual Network Traffic

Unusual and unexpected network traffic is never a good sign. Systems will soon become slow or unresponsive, and it won’t be long until no one can access any services.

A firewall can usually spot unusual network traffic and even stop it. If it doesn’t, you may need to start considering DoS attack mitigation tools like traffic filtering.

4. High CPU or Memory Usage

Certain DoS attacks—like buffer overflows—affect the memory of the systems they target. The first signs will usually include a slower-than-normal system and unresponsive programs. These issues can have other causes, though. High CPU usage could simply be an incompatible program, for instance, while unresponsive services could be caused by a connectivity issue.

You will need to keep an eye on your systems at all times and double-check every time you’re experiencing what could be symptoms of a DoS attack. Connectivity, software, or hardware issues will usually be easy to find and will cease once the culprit is identified and remedied, whereas a DoS attack will get worse until it is stopped.

Conclusion

A denial of service attack prevents legitimate users from accessing a device, service, or network. The disruption can have serious consequences for users and businesses alike and include loss of revenue, reputation, and sensitive data.

DoS attacks come in many forms, including buffer overflows and flooding, with the attack having a single source. You may also encounter distributed denial of service attacks. These are similar to DoS attacks, but they come from multiple IPs, which makes them harder to detect and stop.

The good news is there are ways to prevent DoS attacks. Some are more simple, like using a firewall and educating users about what DoS attacks look like. Others are more complex and involve using load balancing techniques, intrusion detection and prevention systems, encryption, and pen testing.

Keep your systems secure against DoS and DDoS attacks with Gcore’s DDoS protection solution. It can keep your services, apps, and websites safe, and has over 1 Tbps total filtering capacity. Connect with one of our experts to learn more.

Related articles

11 simple tips for securing your APIs

A vast 84% of organizations have experienced API security incidents in the past year. APIs (application programming interfaces) are the backbone of modern technology, allowing seamless interaction between diverse software platforms. However, this increased connectivity comes with a downside: a higher risk of security breaches, which can include injection attacks, credential stuffing, and L7 DDoS attacks, as well as the ever-growing threat of AI-based attacks.Fortunately, developers and IT teams can implement DIY API protection. Mitigating vulnerabilities involves using secure coding techniques, conducting thorough testing, and applying strong security protocols and frameworks. Alternatively, you can simply use a WAAP (web application and API protection) solution for specialized, one-click, robust API protection.This article explains 11 practical tips that can help protect your APIs from security threats and hacking attempts, with examples of commands and sample outputs to provide API security.#1 Implement authentication and authorizationUse robust authentication mechanisms to verify user identity and authorization strategies like OAuth 2.0 to manage access to resources. Using OAuth 2.0, you can set up a token-based authentication system where clients request access tokens using credentials. # Requesting an access token curl -X POST https://yourapi.com/oauth/token \ -d "grant_type=client_credentials" \ -d "client_id=your_client_id" \ -d "client_secret=your_client_secret" Sample output: { "access_token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9...", "token_type": "bearer", "expires_in": 3600 } #2 Secure communication with HTTPSEncrypting data in transit using HTTPS can help prevent eavesdropping and man-in-the-middle attacks. Enabling HTTPS may involve configuring your web server with SSL/TLS certificates, such as Let’s Encrypt with nginx. sudo certbot --nginx -d yourapi.com #3 Validate and sanitize inputValidating and sanitizing all user inputs protects against injection and other attacks. For a Node.js API, use express-validator middleware to validate incoming data. app.post('/api/user', [ body('email').isEmail(), body('password').isLength({ min: 5 }) ], (req, res) => { const errors = validationResult(req); if (!errors.isEmpty()) { return res.status(400).json({ errors: errors.array() }); } // Proceed with user registration }); #4 Use rate limitingLimit the number of requests a client can make within a specified time frame to prevent abuse. The express-rate-limit library implements rate limiting in Express.js. const rateLimit = require('express-rate-limit'); const apiLimiter = rateLimit({ windowMs: 15 * 60 * 1000, // 15 minutes max: 100 }); app.use('/api/', apiLimiter); #5 Undertake regular security auditsRegularly audit your API and its dependencies for vulnerabilities. Runnpm auditin your Node.js project to detect known vulnerabilities in your dependencies.  npm audit Sample output: found 0 vulnerabilities in 1050 scanned packages #6 Implement access controlsImplement configurations so that users can only access resources they are authorized to view or edit, typically through roles or permissions. The two more common systems are Role-Based Access Control (RBAC) and Attribute-Based Access Control (ABAC) for a more granular approach.You might also consider applying zero-trust security measures such as the principle of least privilege (PoLP), which gives users the minimal permissions necessary to perform their tasks. Multi-factor authentication (MFA) adds an extra layer of security beyond usernames and passwords.#7 Monitor and log activityMaintain comprehensive logs of API activity with a focus on both performance and security. By treating logging as a critical security measure—not just an operational tool—organizations can gain deeper visibility into potential threats, detect anomalies more effectively, and accelerate incident response.#8 Keep dependencies up-to-dateRegularly update all libraries, frameworks, and other dependencies to mitigate known vulnerabilities. For a Node.js project, updating all dependencies to their latest versions is vital. npm update #9 Secure API keysIf your API uses keys for access, we recommend that you make sure that they are securely stored and managed. Modern systems often utilize dynamic key generation techniques, leveraging algorithms to automatically produce unique and unpredictable keys. This approach enhances security by reducing the risk of brute-force attacks and improving efficiency.#10 Conduct penetration testingRegularly test your API with penetration testing to identify and fix security vulnerabilities. By simulating real-world attack scenarios, your organizations can systematically identify vulnerabilities within various API components. This proactive approach enables the timely mitigation of security risks, reducing the likelihood of discovering such issues through post-incident reports and enhancing overall cybersecurity resilience.#11 Simply implement WAAPIn addition to taking the above steps to secure your APIs, a WAAP (web application and API protection) solution can defend your system against known and unknown threats by consistently monitoring, detecting, and mitigating risks. With advanced algorithms and machine learning, WAAP safeguards your system from attacks like SQL injection, DDoS, and bot traffic, which can compromise the integrity of your APIs.Take your API protection to the next levelThese steps will help protect your APIs against common threats—but security is never one-and-done. Regular reviews and updates are essential to stay ahead of evolving vulnerabilities. To keep on top of the latest trends, we encourage you to read more of our top cybersecurity tips or download our ultimate guide to WAAP.Implementing specialized cybersecurity solutions such as WAAP, which combines web application firewall (WAF), bot management, Layer 7 DDoS protection, and API security, is the best way to protect your assets. Designed to tackle the complex challenges of API threats in the age of AI, Gcore WAAP is an advanced solution that keeps you ahead of security threats.Discover why WAAP is a non-negotiable with our free ebook

What are zero-day attacks? Risks, prevention tips, and new trends

Zero-day attack is a term for any attack that targets a vulnerability in software or hardware that has yet to be discovered by the vendor or developer. The term “zero-day” stems from the idea that the developer has had zero days to address or patch the vulnerability before it is exploited.In a zero-day attack, an attacker finds a vulnerability before a developer discovers and patches itThe danger of zero-day attacks lies in their unknownness. Because the vulnerabilities they target are undiscovered, traditional defense mechanisms or firewalls may not detect them as no specific patch exists, making attack success rates higher than for known attack types. This makes proactive and innovative security measures, like AI-enabled WAAP, crucial for organizations to stay secure.Why are zero-day attacks a threat to businesses?Zero-day attacks pose a unique challenge for businesses due to their unpredictable nature. Since these exploits take advantage of previously unknown vulnerabilities, organizations have no warning or time to deploy a patch before they are targeted. This makes zero-day attacks exceptionally difficult to detect and mitigate, leaving businesses vulnerable to potentially severe consequences. As a result, zero-day attacks can have devastating consequences for organizations of all sizes. They pose financial, reputational, and regulatory risks that can be difficult to recover from, including the following:Financial and operational damage: Ransomware attacks leveraging zero-day vulnerabilities can cripple operations and lead to significant financial losses due to data breach fines. According to recent studies, the average cost of a data breach in 2025 has surpassed $5 million, with zero-day exploits contributing significantly to these figures.Reputation and trust erosion: Beyond monetary losses, zero-day attacks erode customer trust. A single breach can damage an organization’s reputation, leading to customer churn and lost opportunities.Regulatory implications: With strict regulations like GDPR in the EU and similar frameworks emerging globally, organizations face hefty fines for data breaches. Zero-day vulnerabilities, though difficult to predict, do not exempt businesses from compliance obligations.The threat is made clear by recent successful examples of zero-day attacks. The Log4j vulnerability (Log4Shell), discovered in 2021, affected millions of applications worldwide and was widely exploited. In 2023, the MOVEit Transfer exploit was used to compromise data from numerous government and corporate systems. These incidents demonstrate how zero-day attacks can have far-reaching consequences across different industries.New trends in zero-day attacksAs cybercriminals become more sophisticated, zero-day attacks continue to evolve. New methods and technologies are making it easier for attackers to exploit vulnerabilities before they are discovered. The latest trends in zero-day attacks include AI-powered attacks, expanding attack surfaces, and sophisticated multi-vendor attacks.AI-powered attacksAttackers are increasingly leveraging artificial intelligence to identify and exploit vulnerabilities faster than ever before. AI tools can analyze vast amounts of code and detect potential weaknesses in a fraction of the time it would take a human. Moreover, AI can automate the creation of malware, making attacks more frequent and harder to counter.For example, AI-driven malware can adapt in real time to avoid detection, making it particularly effective in targeting enterprise networks and cloud-based applications. Hypothetically, an attacker could use an AI algorithm to scan for weaknesses in widely used SaaS applications, launching an exploit before a patch is even possible.Expanding attack surfacesThe digital transformation continues to expand the attack surface for zero-day exploits. APIs, IoT devices, and cloud-based services are increasingly targeted, as they often rely on interconnected systems with complex dependencies. A single unpatched vulnerability in an API could provide attackers with access to critical data or applications.Sophisticated multi-vector attacksCybercriminals are combining zero-day exploits with other tactics, such as phishing or social engineering, to create multi-vector attacks. This approach increases the likelihood of success and makes defense efforts more challenging.Prevent zero-day attacks with AI-powered WAAPWAAP solutions are becoming a cornerstone of modern cybersecurity, particularly in addressing zero-day vulnerabilities. Here’s how they help:Behavioral analytics: WAAP solutions use behavioral models to detect unusual traffic patterns, blocking potential exploits before they can cause damage.Automated patching: By shielding applications with virtual patches, WAAP can provide immediate protection against vulnerabilities while a permanent fix is developed.API security: With APIs increasingly targeted, WAAP’s ability to secure API endpoints is critical. It ensures that only authorized requests are processed, reducing the risk of exploitation.How WAAP stops AI-driven zero-day attacksAI is not just a tool for attackers—it is also a powerful ally for defenders. Machine learning algorithms can analyze user behavior and network activity to identify anomalies in real time. These systems can detect and block suspicious activities that might indicate an attempted zero-day exploit.Threat intelligence platforms powered by AI can also predict emerging vulnerabilities by analyzing trends and known exploits. This enables organizations to prepare for potential attacks before they occur.At Gcore, our WAAP solution combines these features to provide comprehensive protection. By leveraging cutting-edge AI and machine learning, Gcore WAAP detects and mitigates threats in real time, keeping web applications and APIs secure even from zero-day attacks.More prevention techniquesBeyond WAAP, layering protection techniques can further enhance your business’ ability to ward off zero-day attacks. Consider the following measures:Implement a robust patch management system so that known vulnerabilities are addressed promptly.Conduct regular security assessments and penetration testing to help identify potential weaknesses before attackers can exploit them.Educate employees about phishing and other social engineering tactics to decease the likelihood of successful attacks.Protect your business against zero-day attacks with GcoreZero-day attacks pose a significant threat to businesses, with financial, reputational, and regulatory consequences. The rise of AI-powered cyberattacks and expanding digital attack surfaces make these threats even more pressing. Organizations must adopt proactive security measures, including AI-driven defense mechanisms like WAAP, to protect their critical applications and data. By leveraging behavioral analytics, automated patching, and advanced threat intelligence, businesses can minimize their risk and stay ahead of attackers.Gcore’s AI-powered WAAP provides the robust protection your business needs to defend against zero-day attacks. With real-time threat detection, virtual patching, and API security, Gcore WAAP ensures that your web applications remain protected against even the most advanced cyber threats, including zero-day threats. Don’t wait until it’s too late—secure your business today with Gcore’s cutting-edge security solutions.Discover how WAAP can help stop zero-day attacks

Why do bad actors carry out Minecraft DDoS attacks?

One of the most played video games in the world, Minecraft, relies on servers that are frequently a target of distributed denial-of-service (DDoS) attacks. But why would malicious actors target Minecraft servers? In this article, we’ll look at why these servers are so prone to DDoS attacks and uncover the impact such attacks have on the gaming community and broader cybersecurity landscape. For a comprehensive analysis and expert tips, read our ultimate guide to preventing DDoS attacks on Minecraft servers.Disruption for financial gainFinancial exploitation is a typical motivator for DDoS attacks in Minecraft. Cybercriminals frequently demand ransom to stop their attacks. Server owners, especially those with lucrative private or public servers, may feel pressured to pay to restore normalcy. In some cases, bad actors intentionally disrupt competitors to draw players to their own servers, leveraging downtime for monetary advantage.Services that offer DDoS attacks for hire make these attacks more accessible and widespread. These malicious services target Minecraft servers because the game is so popular, making it an attractive and easy option for attackers.Player and server rivalriesRivalries within the Minecraft ecosystem often escalate to DDoS attacks, driven by competition among players, servers, hosts, and businesses. Players may target opponents during tournaments to disrupt their gaming experience, hoping to secure prize money for themselves. Similarly, players on one server may initiate attacks to draw members to their server and harm the reputation of other servers. Beyond individual players, server hosts also engage in DDoS attacks to disrupt and induce outages for their rivals, subsequently attempting to poach their customers. On a bigger scale, local pirate servers may target gaming service providers entering new markets to harm their brand and hold onto market share. These rivalries highlight the competitive and occasionally antagonistic character of the Minecraft community, where the stakes frequently surpass in-game achievements.Personal vendettas and retaliationPersonal conflicts can occasionally be the source of DDoS attacks in Minecraft. In these situations, servers are targeted in retribution by individual gamers or disgruntled former employees. These attacks are frequently the result of complaints about unsolved conflicts, bans, or disagreements over in-game behavior. Retaliation-driven DDoS events can cause significant disruption, although lower in scope than attacks with financial motivations.Displaying technical masterySome attackers carry out DDoS attacks to showcase their abilities. Minecraft is a perfect testing ground because of its large player base and community-driven server infrastructure. Successful strikes that demonstrate their skills enhance reputations within some underground communities. Instead of being a means to an end, the act itself becomes a badge of honor for those involved.HacktivismHacktivists—people who employ hacking as a form of protest—occasionally target Minecraft servers to further their political or social goals. These attacks are meant to raise awareness of a subject rather than be driven by personal grievances or material gain. To promote their message, they might, for instance, assault servers that are thought to support unfair policies or practices. This would be an example of digital activism. Even though they are less frequent, these instances highlight the various reasons why DDoS attacks occur.Data theftMinecraft servers often hold significant user data, including email addresses, usernames, and sometimes even payment information. Malicious actors sometimes launch DDoS attacks as a smokescreen to divert server administrators’ attention from their attempts to breach the server and steal confidential information. This dual-purpose approach disrupts gameplay and poses significant risks to user privacy and security, making data theft one of the more insidious motives behind such attacks.Securing the Minecraft ecosystemDDoS attacks against Minecraft are motivated by various factors, including personal grudges, data theft, and financial gain. Every attack reveals wider cybersecurity threats, interferes with gameplay, and damages community trust. Understanding these motivations can help server owners take informed steps to secure their servers, but often, investing in reliable DDoS protection is the simplest and most effective way to guarantee that Minecraft remains a safe and enjoyable experience for players worldwide. By addressing the root causes and improving server resilience, stakeholders can mitigate the impact of such attacks and protect the integrity of the game.Gcore offers robust, multi-layered security solutions designed to shield gaming communities from the ever-growing threat of DDoS attacks. Founded by gamers for gamers, Gcore understands the industry’s unique challenges. Our tools enable smooth gameplay and peace of mind for both server owners and players.Want an in-depth look at how to secure your Minecraft servers?Download our ultimate guide

What is a DDoS attack?

A DDoS (distributed denial-of-service) attack is a type of cyberattack in which a hacker overwhelms a server with an excessive number of requests, causing the server to stop functioning properly. This can cause the website, app, game, or other online service to become slow, unresponsive, or completely unavailable. DDoS attacks can result in lost customers and revenue for the victim. DDoS attacks are becoming increasingly common, with a 46% increase in the first half of 2024 compared to the same period in 2023.How do DDoS attacks work?DDoS attacks work by overwhelming and flooding a company’s resources so that legitimate users cannot get through. The attacker creates huge amounts of malicious traffic by creating a botnet, a collection of compromised devices that work together to carry out the attack without the device owners’ knowledge. The attacker, referred to as the botmaster, sends instructions to the botnet in order to implement the attack. The attacker forces these bots to send an enormous amount of internet traffic to a victim’s resource. As a result, the server can’t process real users trying to access the website or app. This causes customer dissatisfaction and frustration, lost revenue, and reputational damage for companies.Think of it this way: Imagine a vast call center. Someone dials the number but gets a busy tone. This is because a single spammer has made thousands of automated calls from different phones. The call center’s lines are overloaded, and the legitimate callers cannot get through.DDoS attacks work similarly, but online: The fraudster’s activity completely blocks the end users from reaching the website or online service.Different types of DDoS attacksThere are three categories of DDoS attacks, each attacking a different network communication layer. These layers come from the OSI (Open Systems Interconnection) model, the foundational framework for network communication that describes how different systems and devices connect and communicate. This model has seven layers. DDoS attacks seek to exploit vulnerabilities across three of them: L3, L4, and L7.While all three types of attacks have the same end goal, they differ in how they work and which online resources they target. L3 and L4 DDoS attacks target servers and infrastructure, while L7 attacks affect the app itself.Volumetric attacks (L3) overwhelm the network equipment, bandwidth, or server with a high volume of traffic.Connection protocol attacks (L4) target the resources of a network-based service, like website firewalls or server operating systems.Application layer attacks (L7) overwhelm the network layer, where the application operates with many malicious requests, which leads to application failure.1. Volumetric attacks (L3)L3, or volumetric, DDoS attacks are the most common form of DDoS attack. They work by flooding internal networks with malicious traffic, aiming to exhaust bandwidth and disrupt the connection between the target network or service and the internet. By exploiting key communication protocols, attackers send massive amounts of traffic, often with spoofed IP addresses, to overwhelm the victim’s network. As the network equipment strains to process this influx of data, legitimate requests are delayed or dropped, leading to service degradation or even complete network failure.2. Connection protocol attacks (L4)Protocol attacks occur when attackers send connection requests from multiple IP addresses to target server open ports. One common tactic is a SYN flood, where attackers initiate connections without completing them. This forces the server to allocate resources to these unfinished sessions, quickly leading to resource exhaustion. As these fake requests consume the server’s CPU and memory, legitimate traffic is unable to get through. Firewalls and load balancers managing incoming traffic can also be overwhelmed, resulting in service outages.3. Application layer attacks (L7)Application layer attacks strike at the L7 layer, where applications operate. Web applications handle everything from simple static websites to complex platforms like e-commerce sites, social media networks, and SaaS solutions. In an L7 attack, a hacker deploys multiple bots or machines to repeatedly request the same resource until the server becomes overwhelmed.By mimicking genuine user behavior, attackers flood the web application with seemingly legitimate requests, often at high rates. For example, they might repeatedly submit incorrect login credentials or overload the search function by continuously searching for products. As the server consumes its resources managing these fake requests, genuine users experience slow response times or may be completely denied access to the application.How can DDoS attacks be prevented?To stay one step ahead of attackers, use a DDoS protection solution to protect your web resources. A mitigation solution detects and blocks harmful DDoS traffic sent by attackers, keeping your servers and applications safe and functional. If an attacker targets your server, your legitimate users won’t notice any change—even during a considerable attack—because the protection solution will allow safe traffic while identifying and blocking malicious requests.DDoS protection providers also give you reports on attempted DDoS attacks. This way, you can track when the attack happened, as well as the size and scale of the attack. This enables you to respond effectively, analyze the potential implications of the attack, and implement risk management strategies to mitigate future disruptions.Repel DDoS attacks with GcoreAt Gcore, we offer robust and proven security solutions to protect your business from DDoS attacks. Gcore DDoS Protection provides comprehensive mitigation at L3, L4, and L7 for websites, apps, and servers. We also offer L7 protection as part of Gcore WAAP, which keeps your web apps and APIs secure against a range of modern threats using AI-enabled threat detection.Take a look at our recent Radar report to learn more about the latest DDoS attack trends and the changing strategies and patterns of cyberattacks.Read our DDoS Attack Trends Radar report

How to Spot and Stop a DDoS Attack

The faster you detect and resolve a DDoS (distributed denial-of-service) attack, the less damage it can do to your business. Read on to learn how to identify the signs of a DDoS attack, differentiate it from other issues, and implement effective protection strategies to safeguard your business. You’ll also discover why professional mitigation is so important for your business.The Chronology of a DDoS AttackThe business impact of a DDoS attack generally increases the longer it continues. While the first few minutes might not be noticeable without a dedicated solution with monitoring capabilities, your digital services could be taken offline within an hour. No matter who your customer is or how you serve them, every business stands to lose customers, credibility, and revenue through downtime.The First Few Minutes: Initial Traffic SurgeAttackers often start with a low-volume traffic flow to avoid early detection. This phase, known as pre-flooding, evaluates the target system’s response and defenses. You may notice a slight increase in traffic, but it could still be within the range of normal fluctuations.Professional DDoS mitigation services use algorithms to spot these surges, identify whether the traffic increase is malicious, and stop attacks before they can have an impact. Without professional protection, it’s almost impossible to spot this pre-flooding phase, leading you into the following phases of an attack.The First Hour: Escalating TrafficThe attack will quickly escalate, resulting in a sudden and extreme increase in traffic volume. During this stage, network performance will start to degrade noticeably, causing unusually slow loading times for websites and services.Look out for network disconnections, or unusually slow performance. These are telltale signs of a DDoS attack in its early stages.The First Few Hours: Service DisruptionAs the attack intensifies, the website may become completely inaccessible. You might experience an increased volume of spam emails as part of a coordinated effort to overwhelm your systems. Frequent loss of connectivity within the local network can occur as the attack overloads the infrastructure.You can identify this stage by looking for website or network unavailability. Users will experience continuous problems when trying to connect to the targeted application or server.Within 24 Hours: Sustained ImpactIf the attack continues, the prolonged high traffic volume will cause extended service outages and significant slowdowns. By this point, it is clear that a DDoS attack is in progress, especially if multiple indicators are present simultaneously.By now, not only is your website and/or network unavailable, but you’re also at high risk of data breaches due to the loss of control of your digital resources.Distinguishing DDoS Attacks from Other IssuesWhile DDoS attack symptoms like slow performance and service outages are common, they can also be caused by other problems. Here’s how to differentiate between a DDoS attack and other issues:AspectDDoS attackHosting problemsLegitimate traffic spikeSoftware issuesTraffic volumeSudden, extreme increaseNo significant increaseHigh but expected during peaksNormal, higher, lower, or zeroService responseExtremely slow or unavailableSlow or intermittentSlower but usually functionalErratic, with specific errorsError messagesFrequent Service UnavailableInternal Server Error, TimeoutNo specific errors, slower responsesSpecific to the softwareDurationProlonged, until mitigatedVaries, often until resolvedTemporary, during peaks, often predictableVaries based on the bugSource of trafficMultiple, distributed, malicious signaturesConsistent with normal traffic, localizedGeographically diverse, consistent patternsDepends on the user baseProtective Strategies Against DDoS AttacksPrevention is the best defense against DDoS attacks. Here are some strategies to protect your business:Content delivery networks (CDNs): CDNs distribute your traffic across multiple servers worldwide, reducing the load on any single server and mitigating the impact of DDoS attacks.DDoS protection solutions: These services provide specialized tools to detect, mitigate, and block DDoS attacks. They continuously monitor traffic patterns in real time to detect anomalies and automatically respond to and stop attacks without manual intervention.Web application and API protection (WAAP): WAAP solutions protect web applications and APIs from a wide range of threats, including DDoS attacks. They use machine learning and behavioral analysis to detect and block sophisticated attacks, from DDoS assaults to SQL injections.Gcore provides all three protection strategies in a single platform, offering your business the security it needs to thrive in a challenging threat landscape.Don’t Delay, Protect Your Business NowGcore provides comprehensive DDoS protection, keeping your services online and your business thriving even during an attack. Explore Gcore DDoS Protection or get instant protection now.Discover the latest DDoS trends and threats in our H3 2023 report

Improve Your Privacy and Data Security with TLS Encryption on CDN

The web is a public infrastructure: Anyone can use it. Encryption is a must to ensure that communications over this public infrastructure are secure and private. You don’t want anyone to read or modify the data you send or receive, like credit card information when paying for an online service.TLS encryption is a basic yet crucial safeguard that ensures only the client (the user’s device, like a laptop) and server can read your request and response data; third parties are locked out. You can run TLS on a CDN for improved performance, caching, and TLS management. If you want to learn more about TLS and how running it on a CDN can improve your infrastructure, this is the right place to start.What Is TLS Encryption and Why Does It Matter?TLS, transport layer security, encrypts data sent via the web to prevent it from being seen or changed while it’s in transit. For that reason, it’s called encryption in-transit technology. TLS is also commonly called HTTPS when used with HTTP or SSL, as previous versions of the technology were based on it. TLS ensures high encryption performance and forward secrecy. To learn more about encryption, check out our dedicated article.TLS is a vital part of the web because it ensures trust for end users and search engines alike. End users can rest assured that their data—like online banking information or photos of their children—can’t be accessed. Search engines know that information protected by TLS is trustworthy, so they rate it higher than non-protected content.What’s the Connection Between TLS and CDN?A CDN, or content delivery network, helps improve your website’s performance by handling the delivery of your content from its own servers rather than your website’s server. When a CDN uses TLS, it ensures that your content is encrypted as it travels from your server to the CDN and from the CDN to your users.With TLS offloading, your server only needs to encrypt the content for each CDN node, not for every individual user. This reduces the workload on your server.Here’s a simple breakdown of how it works:Your server encrypts the content once and sends it to the CDN.The CDN caches this encrypted content.When a user requests the content, the CDN serves it directly to them, handling all encryption and reducing the need to repeatedly contact your server.Without a CDN, your server would have to encrypt and send content to each user individually, which can slow things down. With a CDN, your server encrypts the content once for the CDN. The CDN then takes over, encrypting and serving the content to all users, speeding up the process and reducing the load on your server.Figure 1: Comparison of how content is served with TLS on the web server (left) vs on CDN (right)Benefits of “Offloading” TLS to a CDNOffloading TLS to a CDN can improve your infrastructure with improved performance, better caching, and simplified TLS management.Increased PerformanceWhen establishing a TLS connection, the client and server must exchange information to negotiate a session key. This exchange involves four messages being sent over the network, as shown in Figure 2. The higher the latency between the two participants, the longer it takes to establish the connection. CDN nodes are typically closer to the client, resulting in lower latency and faster connection establishment.As mentioned above, CDN nodes handle all the encryption tasks. This frees up your server’s resources for other tasks and allows you to simplify its code base.Figure 2: TLS handshakeImproved CachingIf your data is encrypted, the CDN can’t cache it. A single file will look different from the CDN nodes for every new TLS connection, eliminating the CDN benefits (Figure 3). If the CDN holds the certificates, it can negotiate encryption with the clients and collect the files from your server in plaintext. This allows the CDN to cache the content efficiently and serve it faster to users.Figure 3: TLS and CDN caching comparedSimplified TLS ManagementThe CDN takes care of maintenance tasks such as certificate issuing, rotation, and auto-renewal. With the CDN managing TLS, your server’s code base can be simplified, and you no longer need to worry about potential TLS updates in the future.TLS Encryption with Gcore CDNWith the Gcore CDN we don’t just take care of your TLS encryption, but also file compression and DNS lookups. This way, you can unburden your servers from non-functional requirements, which leads to smaller, easier-to-maintain code bases, lower CPU, memory, and traffic impact, and a lower workload for the teams managing those servers.Gcore CDN offers two TLS offloading options:Free Let’s Encrypt certificates with automatic validation, an effective and efficient choice for simple security needsPaid custom certificates, ideal if your TLS setup has more complex requirementsHow to Enable HTTPS with a Free Let’s Encrypt CertificateSetting up HTTPS for your website is quick, easy, and free. First, make sure you have a Gcore CDN resource for your website. If you haven’t created one yet, you can do so in the Gcore Customer Portal by clicking Create CDN resource in the top-right of the window (Figure 4) and following the setup wizard. You’ll be asked to update your DNS records so they point to the Gcore CDN, allowing Gcore to issue the certificates later.Figure 4: Create CDN resourceNext, open the resource settings by selecting your CDN resource from the list in the center (Figure 5).Figure 5: Select the CDN resourceEnable HTTPS in the resource settings, as shown in Figure 6:Select SSL in the left navigationClick the Enable HTTPS checkboxClick Get SSL certificateFigure 6: Get an SSL certificateYour certificate will usually be issued within 30 minutes.Our Commitment to Online SecurityAt Gcore, we’re committed to making the internet secure for everyone. As part of this mission, we offer free CDN and free TLS certificates. Take advantage and protect your resources efficiently for free!Get TLS encryption on Gcore CDN free

Subscribe to our newsletter

Get the latest industry trends, exclusive insights, and Gcore updates delivered straight to your inbox.