DDoS Examples: 10 DDoS Attacks that Took the World by Storm

• Types of DDoS Attacks
• 10 Notable DDoS Attack Examples

• Best Practices for Defending Against DDoS Attacks
• Radware’s DDoS Prevention Tools

In May 2024, the Internet Archive faced a series of DDoS attacks that intermittently disrupted its services over several days. The hacker group SN_BLACKMETA claimed responsibility for these attacks, which drew comparisons to the 2023 British Library cyberattack.

Later, in October 2024, the Internet Archive suffered another breach, resulting in the exposure of approximately 31 million user accounts. The attackers accessed users' email addresses and bcrypt-hashed passwords, leading to significant service outages as the organization worked to secure its systems.

Anonymous Sudan emerged in early 2023 as a hacktivist group conducting large-scale DDoS attacks against various global targets. Their operations included over 35,000 DDoS attacks on organizations such as Microsoft, OpenAI, and multiple healthcare facilities. In October 2024, U.S. authorities indicted two Sudanese nationals for their alleged roles in these cyberattacks, revealing that the group's activities caused over $10 million in damages to U.S. victims.

The indictment also detailed the group's use of a distributed cloud attack tool (DCAT), known as "Godzilla," "Skynet," or "InfraShutdown," to facilitate their attacks.

In early 2023, Microsoft Azure faced one of the largest distributed denial-of-service (DDoS) attacks ever recorded, peaking at a staggering 3.47 terabits per second (Tbps). This massive assault, attributed to a botnet leveraging vulnerable devices across the globe, targeted Microsoft’s cloud infrastructure, aiming to disrupt services for its enterprise clients. The attack exploited sophisticated techniques, including multiple traffic vectors and amplified reflection, to overwhelm Azure's systems.

Microsoft's advanced DDoS protection mechanisms successfully mitigated the attack, ensuring no significant service disruptions. This event underscored the increasing scale of DDoS threats in the cloud era and the critical need for robust, layered defenses in cloud environments. It also highlighted the importance of adaptive threat intelligence and real-time mitigation strategies to counter the evolving tactics of cybercriminals.

In February 2020, AWS experienced a massive DDoS attack peaking at 2.3 Tbps, one of the largest ever recorded. This strike lasted for three days and exemplified how attackers could reach tremendous levels of traffic by exploiting infrastructure limitations and flaws within network designs. The specifics of the attack were not publicly detailed, but it demonstrated the capabilities of modern DDoS strategies to target sophisticated cloud services.

AWS effectively mitigated the threat using its global DDoS protection infrastructure, proving the importance of adopting scalable defense mechanisms. This incident highlighted both the evolving nature of DDoS attacks and the imperative for cloud providers to stay ahead in their defensive capabilities.

In February 2018, GitHub experienced one of the largest DDoS attacks recorded at the time, reaching peak traffic of 1.35 Tbps. Unlike traditional botnet-based attacks, this onslaught exploited a technique known as Memcached amplification, where attackers used misconfigured Memcached servers to amplify the volume of traffic directed at GitHub. This approach allowed the attackers to launch a massive assault without a large botnet at their disposal.

Despite its large scale, GitHub managed to mitigate the attack within minutes, thanks to its partnerships with strong DDoS protection services that absorbed the traffic through their infrastructure. This incident highlighted the effectiveness of having real-time response strategies in place, as well as the importance of swift collaboration with third-party network security providers during periods of intense cyber-threat levels.

In September 2017, Google was hit by what was, at the time, the largest DDoS attack ever recorded, with traffic peaking at 2.54 Tbps. Google only disclosed details of the attack in 2020, revealing it as a state-sponsored attack, allegedly originating from Chinese threat actors. The attackers used a combination of thousands of IP addresses, often hijacked from unprotected devices across the internet, to generate and direct the immense traffic surge toward Google’s servers.

This level of traffic could have overwhelmed less-prepared targets, but Google’s advanced DDoS protection measures, which include an extensive global infrastructure and layered defense mechanisms, managed to absorb the traffic. The disclosure of this attack was significant as it highlighted the ability of state-sponsored groups to mobilize massive resources to achieve strategic cyber goals.

The Mirai botnet, first identified in 2016, is infamous for launching large-scale DDoS attacks by exploiting thousands of IoT devices with inadequate security. This botnet targeted manageable devices like IP cameras and home routers infected by malware, converting them into bots. With these compromised devices, Mirai orchestrated an outage on major platforms, including Twitter, Netflix, and Reddit, by attacking Dyn, a major domain name system (DNS) provider.

The Mirai attacks underscored significant vulnerabilities in IoT device design, particularly regarding poorly secured systems susceptible to exploitation. The implications of these attacks emphasized the need for enhanced security protocols within IoT devices and urged manufacturers to implement better safety measures. Mirai also asserted the sheer power and potential devastation botnets could unleash, changing how cybersecurity measures address IoT vulnerabilities.

In 2014, during the Occupy Central protests for democratic reform in Hong Kong, protesters relied on digital platforms to organize and communicate. Platforms like FireChat, a peer-to-peer messaging application that doesn’t rely on a central network, played a crucial role as protest organizers coordinated with each other. During this period, however, many protest-related sites and apps came under DDoS attacks, which are believed to have been politically motivated.

These attacks reached extraordinary volumes, reportedly in the tens of gigabits per second, intending to disrupt the communication networks of activists and inhibit their ability to organize. This incident highlighted the vulnerabilities of digital tools that activists and civilians depend on in politically sensitive situations. The attack brought global awareness to the cybersecurity needs of civic tech platforms and underscored how DDoS attacks could be weaponized to destabilize political movements.

In 2013, Spamhaus, a non-profit organization focused on tracking spam and related cyber threats, became the target of a massive DDoS attack that nearly broke the internet’s capacity at the time. Reaching an unprecedented 300 Gbps, this attack leveraged a DNS amplification technique, where attackers exploited open DNS resolvers to amplify traffic. By sending small DNS requests with spoofed IP addresses to numerous servers, the attackers directed massive volumes of traffic toward Spamhaus's servers.

The onslaught temporarily overwhelmed Spamhaus’s systems and even caused delays in other parts of the internet due to traffic congestion. This attack drew international attention to the potential for misconfigured DNS servers to be used as a “force multiplier” in DDoS attacks, leading to intensified efforts to secure the DNS ecosystem. It also pushed organizations to consider layered DDoS defenses to handle such high-intensity attacks.

The 2007 cyberattack on Estonia is one of the first significant examples of DDoS attacks with geopolitical underpinnings. Following a political dispute with Russia over the relocation of a Soviet-era statue, Estonian government, media, and banking websites experienced sustained DDoS attacks. These attacks disrupted essential services for weeks, blocking citizens' access to online banking, government communications, and news outlets.

The scale and sophistication of the attacks were unprecedented at the time, crippling the nation’s internet infrastructure and isolating Estonia digitally. This experience highlighted the need for national cybersecurity strategies, as Estonia recognized the vulnerability of its digital infrastructure. The attacks led Estonia to push for stronger cybersecurity defense within NATO, and eventually, the NATO Cooperative Cyber Defence Centre of Excellence was established in Estonia’s capital, Tallinn.

Implementing dedicated DDoS protection services is a crucial step in safeguarding businesses against attacks. These services often involve using cloud-based solutions that can absorb large volumes of traffic and filter malicious data before it reaches the targeted network. Companies should consider partnering with specialized providers who offer customizable layers of defense tailored to specific business needs and industry requirements.

DDoS protection services often come with the added benefit of 24/7 monitoring and incident response support. This real-time oversight allows for the rapid identification and neutralization of attack vectors, minimizing potential disruption and damage to operations. Incorporating such services into a security strategy helps secure a business’s reputation and operational resilience.

Regular updates to security infrastructure are essential to maintaining a defense against DDoS attacks and other cyber threats. Outdated systems can expose vulnerabilities that attackers may exploit. Businesses should consistently apply security patches and software updates to close gaps and enhance systems’ ability to repel sophisticated attacks. This includes updating firewalls, intrusion detection systems, and network hardware configurations.

Automation tools can streamline processes, ensuring timely and accurate updates across complex infrastructures. Moreover, conducting regular audits of the security system's integrity allows organizations to identify areas needing adjustment or improvement. By diligently maintaining modernized defenses and infrastructure, businesses equip themselves to efficiently counter emerging threats and secure their data, processes, and reputations against potential DDoS attacks.

An effective incident response plan is vital for minimizing damage during a DDoS attack. Such a plan involves predefined protocols addressing immediate response, communication strategies, and recovery processes. Engaging key stakeholders, including IT, legal, and communications teams is critical to ensure roles and responsibilities are clear for efficient coordination in crisis situations.

Post-attack analysis should be incorporated into the response plans to improve future defenses. By assessing the root cause, impact, and mitigation effectiveness, organizations can refine their strategies and bolster their resilience against future incidents. Developing and rehearsing an incident response plan ensures readiness and equips businesses to minimize operational disruption and maintain customer trust when faced with DDoS and other cyber threats.

Effectively monitoring network traffic patterns can provide early warning signs of a potential DDoS attack. By establishing baseline norms for network performance, businesses can quickly detect anomalies indicative of malicious activity. Continuous monitoring tools can automatically flag and alert security teams to irregularities in traffic volume, packet types, or access attempts, prompting immediate investigation and mitigating threats before they escalate.

Adopting real-time analytics powered by machine learning or AI can enhance the accuracy and speed of anomaly detection. These technologies adapt to an organization’s unique network environment, identifying even subtle changes in behavior that might signify a threat. Integrating proactive traffic monitoring within overall security strategies is essential to effectively combat DDoS and other related network-based threats, ensuring continued service availability and integrity.

Employee training and awareness programs play a crucial role in defense against DDoS attacks and other cyber threats. Ensuring that staff are knowledgeable about safe internet practices, recognizing phishing attempts and understanding the potential threats becomes an integral part of a broader cybersecurity strategy. Regularly updating training materials and conducting penetration tests can help assess and improve the organization’s human defenses.

Comprehensive training should focus not only on recognizing warning signs but also on reporting mechanisms and response protocols in the event of an attack. Empowering employees with the knowledge and tools to act appropriately significantly reduces the likelihood of successful exploitations. This awareness fosters a security-focused culture within the organization, enhancing overall resilience against DDoS attacks and other potential cyber threats.