--- title: Cloudflare's Defense Against the Record-Breaking 7.3... description: Cloudflare successfully mitigated a record-breaking 7.3 Tbps DDoS attack in May 2025, which targeted a hosting provider with 37.4 TB of junk traffic over 45... canonical: https://daily.dev/posts/cloudflare-s-defense-against-the-record-breaking-7-3-tbps-ddos-attack-b2r68yzlt twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Cloudflare's Defense Against the Record-Breaking 7.3 Tbps DDoS Attack | daily.dev og:description: Cloudflare successfully mitigated a record-breaking 7.3 Tbps DDoS attack in May 2025, which targeted a hosting provider with 37.4 TB of junk traffic over 45... og:url: https://daily.dev/posts/cloudflare-s-defense-against-the-record-breaking-7-3-tbps-ddos-attack-b2r68yzlt og:image: https://api.daily.dev/og/posts/B2r68Yzlt.png og:image:alt: Cloudflare's Defense Against the Record-Breaking 7.3 Tbps DDoS Attack og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Cloudflare's Defense Against the Record-Breaking 7.3 Tbps DDoS Attack **[Collections](https://daily.dev/sources/collections)** · 2 min read · 1 upvotes · 0 comments ## Summary Cloudflare successfully mitigated a record-breaking 7.3 Tbps DDoS attack in May 2025, which targeted a hosting provider with 37.4 TB of junk traffic over 45 seconds. The attack originated from over 122,000 IP addresses across 161 countries using UDP floods, QOTD reflection, and NTP amplification techniques. Cloudflare's autonomous protection system with eBPF-based filtering and machine learning algorithms across 477 data centers neutralized the threat without service disruption, surpassing previous records and highlighting the escalating scale of modern cyber attacks. ## Content #Cloudflare Blocks Record-Breaking 7.3 Tbps DDoS Attack Targeting Hosting Provider In May 2025, Cloudflare successfully defended against a monumental distributed denial-of-service (DDoS) attack that reached an unprecedented scale, delivering 7.3 terabits per second (Tbps) of junk traffic. Over the span of just 45 seconds, a staggering 37.4 terabytes (TB) of data hammered the targeted hosting provider, marking a new record in DDoS attack scale. ##Attack Characteristics The assault originated from more than 122,000 unique IP addresses distributed across 161 countries, utilizing a combination of attack vectors such as UDP flood techniques, QOTD reflection, and NTP amplification. These methods were chosen for their efficiency in overwhelming target systems, as they require no connection handshakes, thereby inundating the target with massive volumes of packets. Specifically, the attack targeted nearly 22,000 ports on a single IP address with UDP floods known for their capacity to carpet bomb systems with data, forcing the host to respond futilely until overwhelmed. ##Cloudflare's Response Cloudflare's autonomous DDoS protection system, leveraging eBPF-based filtering and advanced machine learning algorithms, detected and mitigated the attack across its impressive network of 477 data centers globally. The system acted swiftly, activating defensive measures to absorb and neutralize the massive traffic inflow without impacting the hosting provider's operations or customer access. ##Context of Attack This attack surpassed previously noted records of 5.6 Tbps and 6.5 Tbps mitigations earlier in the year, underscoring a rising trend in DDoS attack intensity and complexity. Concurrently, Cloudflare reported other cyber threats, notably involving the RapperBot botnet, which targeted AI company DeepSeek with extortion attempts. As DDoS attacks grow in scale and sophistication, advancements in mitigation technologies, like those employed by Cloudflare, remain crucial for securing internet infrastructure against evolving threats. ## Similar posts on daily.dev - [Don’t just attend KubeCon \+ CloudNativeCon, Merge Forward your experience\!](https://daily.dev/posts/don-t-just-attend-kubecon-cloudnativecon-merge-forward-your-experience--l0rpp73x8) · CNCF · 1 upvotes · 0 comments - [Announcing H2 2026 KCDs](https://daily.dev/posts/announcing-h2-2026-kcds-m96goajm1) · CNCF · 1 upvotes · 0 comments - [Two months of Open Community Groups](https://daily.dev/posts/two-months-of-open-community-groups-asf52zhbs) · CNCF · 0 upvotes · 0 comments - [CNCF Unveils Schedule for KubeCon \+ CloudNativeCon Europe 2026](https://daily.dev/posts/cncf-unveils-schedule-for-kubecon-cloudnativecon-europe-2026-ikhcoa5cb) · CNCF · 2 upvotes · 0 comments - [CNCF Debuts KubeCon \+ CloudNativeCon Japan 2026 Schedule](https://daily.dev/posts/cncf-debuts-kubecon-cloudnativecon-japan-2026-schedule-xp5pyudub) · CNCF · 1 upvotes · 0 comments --- Tags: [#machine-learning](https://daily.dev/tags/machine-learning), [#cyber](https://daily.dev/tags/cyber), [#linux](https://daily.dev/tags/linux), [#cloudflare](https://daily.dev/tags/cloudflare) [View this post on daily.dev](https://daily.dev/posts/cloudflare-s-defense-against-the-record-breaking-7-3-tbps-ddos-attack-b2r68yzlt) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Cloudflare's Defense Against the Record-Breaking 7.3 Tbps DDoS Attack","url":"https://daily.dev/posts/cloudflare-s-defense-against-the-record-breaking-7-3-tbps-ddos-attack-b2r68yzlt","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/cloudflare-s-defense-against-the-record-breaking-7-3-tbps-ddos-attack-b2r68yzlt"},"datePublished":"2025-06-20T10:41:32.796Z","dateModified":"2025-06-20T20:22:26.850Z","description":"Cloudflare successfully mitigated a record-breaking 7.3 Tbps DDoS attack in May 2025, which targeted a hosting provider with 37.4 TB of junk traffic over 45...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2d2be4c846c20f98590666a87f135921?_a=AQAEulh","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2d2be4c846c20f98590666a87f135921?_a=AQAEulh","isAccessibleForFree":true,"articleSection":"Collections","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Collections","logo":"https://media.daily.dev/image/upload/s--fk_6ycEi--/f_auto,q_auto/v1780996001/logos/collections?_a=BAMAMiWQ0","url":"https://daily.dev/sources/collections"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/cloudflare-s-defense-against-the-record-breaking-7-3-tbps-ddos-attack-b2r68yzlt","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"machine-learning,cyber,linux,cloudflare","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Collections","item":"https://daily.dev/sources/collections"},{"@type":"ListItem","position":3,"name":"Cloudflare's Defense Against the Record-Breaking 7.3 Tbps DDoS Attack"}]} ```