--- title: "Cloudflare thwarted the largest DDoS attack in its history — ZEBR.ai" description: "The attack, at 17.2 million rps, was three times larger than the previous largest known DDoS attack" url: "https://zebr.ai/en/blog/cloudflare-thwarted-the-largest-ddos-attack-in-its-history" markdown_url: "https://zebr.ai/en/blog/cloudflare-thwarted-the-largest-ddos-attack-in-its-history.md" language: "en" published: "2021-09-14T08:01:54+00:00" alternates: cs: "https://zebr.ai/cs/blog/cloudflare-odvratil-nejvetsi-ddos-utok-ve-sve-historii.md" sl: "https://zebr.ai/sl/blog/cloudflare-je-preprecil-najvecji-ddos-napad-v-svoji-zgodovini.md" sk: "https://zebr.ai/sk/blog/cloudflare-odvratil-najvacsi-ddos-utok-vo-svojej-historii.md" hr: "https://zebr.ai/hr/blog/cloudflare-odbio-najveci-ddos-napad-u-svojoj-povijesti.md" sr-Latn: "https://zebr.ai/sr-latn/blog/cloudflare-odbio-najveci-ddos-napad-u-svojoj-istoriji.md" bs: "https://zebr.ai/bs/blog/cloudflare-odbio-najveci-ddos-napad-u-svojoj-historiji.md" sq: "https://zebr.ai/sq/blog/cloudflare-zmbrapsi-sulmin-me-te-madh-ddos-ne-historine-e-saj.md" fr: "https://zebr.ai/fr/blog/cloudflare-a-repousse-la-plus-grande-attaque-ddos-de-son-histoire.md" es: "https://zebr.ai/es/blog/cloudflare-repelio-el-mayor-ataque-ddos-de-su-historia.md" de: "https://zebr.ai/de/blog/cloudflare-wehrte-den-groessten-ddos-angriff-seiner-geschichte-ab.md" pt-BR: "https://zebr.ai/pt-br/blog/cloudflare-mitigou-o-maior-ataque-ddos-de-sua-historia.md" pl: "https://zebr.ai/pl/blog/cloudflare-odparl-najwiekszy-atak-ddos-w-swojej-historii.md" it: "https://zebr.ai/it/blog/cloudflare-ha-respinto-il-piu-grande-attacco-ddos-della-sua-storia.md" nl: "https://zebr.ai/nl/blog/cloudflare-heeft-de-grootste-ddos-aanval-in-zijn-geschiedenis-afgeslagen.md" hu: "https://zebr.ai/hu/blog/cloudflare-tortenetenek-legnagyobb-ddos-tamadasat-haritotta-el.md" ro: "https://zebr.ai/ro/blog/cloudflare-a-respins-cel-mai-mare-atac-ddos-din-istoria-sa.md" tr: "https://zebr.ai/tr/blog/cloudflare-tarihindeki-en-buyuk-ddos-saldirisini-engelledi.md" id: "https://zebr.ai/id/blog/cloudflare-menangkis-serangan-ddos-terbesar-dalam-sejarahnya.md" --- [Home](https://zebr.ai/en/) [Blog](https://zebr.ai/en/blog) Cloudflare thwarted the largest DDoS attack in its history # Cloudflare thwarted the largest DDoS attack in its history [Cloudflare](https://zebr.ai/en/blog?tag=cloudflare) [DDoS](https://zebr.ai/en/blog?tag=ddos) [malware and antivirus](https://zebr.ai/en/blog?tag=malware-and-antivirus) [press release](https://zebr.ai/en/blog?tag=press-releases) [web applications](https://zebr.ai/en/blog?tag=web-applications) The attack, at 17.2 million rps, was three times larger than the previous largest known DDoS attack 14/09/2021 · 3 min read · ZEBR.ai editorial team *The attack, at 17.2 million rps, was three times larger than the previous largest known DDoS attack* **PRAGUE, September 14, 2021** – [**Cloudflare**](https://www.cloudflare.com/) announced that this summer it successfully thwarted an attack of **17.2 million requests per second (rps),** which was three times greater than any previously known attack. For comparison, this single attack reached 68% of the average legitimate HTTP traffic, i.e. 25 million requests per second, that Cloudflare recorded in its data centers during the second quarter. The attack, which targeted a Cloudflare customer in the financial sector, was carried out using a highly powerful botnet. It was able to flood the Cloudflare infrastructure protecting the customer's systems with a total of 330 million requests. According to Cloudflare's findings, the attack came from more than 20,000 bots in 125 countries around the world – most of them were located in Indonesia, India and Brazil. The attack was automatically detected and thwarted using Cloudflare's autonomous edge system for DDoS protection. Massive attacks, particularly on banking organizations worldwide, are becoming increasingly common, but local financial institutions are not spared either. In connection with recent issues affecting the websites of global companies, problems were also reported by Czech and Slovak clients, who were unable to log in to internet banking or mobile banking for a period of time. “While most attacks are smaller and short-lived, we are increasingly witnessing massive, high-volume attacks today,” said **Michal Hebeda, Sales Engineer at ZEBRA SYSTEMS.** “What is important, however, is that these high-volume short-term attacks hit infrastructure protected by outdated DDoS systems the hardest, as well as organizations that do not have active protection based on automated cloud solutions.” In the Czech Republic and Slovakia, **ZEBRA SYSTEMS** is responsible for delivering Cloudflare services focused on application and network infrastructure security (including, for example, Cloudflare DDoS and WAF), improving the performance and reliability of internet applications (Cloudflare CDN and DNS), team collaboration (Cloudflare for Teams, Cloudflare Access), and developer platforms (Cloudflare Workers). **About Cloudflare** Cloudflare's mission is to help build a better internet. Its platform protects and accelerates any internet application online, without the need for additional hardware, software installation, or code changes. With Cloudflare's support, all web traffic is routed through an intelligent global network that continuously improves with every request. The result is a significant increase in performance and a reduction in spam and other attacks. Cloudflare is a global company headquartered in San Francisco. More at [www.cloudflare.com](http://www.cloudflare.com/). 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