Security | Threat Detection | Cyberattacks | DevSecOps | Compliance

Welcome to the 22nd edition of the Cloudflare DDoS Threat Report. Published quarterly, this report offers a comprehensive analysis of the evolving threat landscape of Distributed Denial of Service (DDoS) attacks based on data from the Cloudflare network. In this edition, we focus on the second quarter of 2025. June was the busiest month for DDoS attacks in 2025 Q2, accounting for nearly 38% of all observed activity.

Cloudflare’s SASE platform is on a mission to strengthen our platform-wide support for hostname- and domain-based policies. This mission is being driven by enthusiastic demands from our customers, and boosted along the way by several interesting engineering challenges. Today, we’re taking a deep dive into the first milestone of this mission, which we recently released in open beta: egress policies by hostname, domain, content category, and application. Let’s dive right in!

Almost 30 years ago, two graduate students at Stanford University — Larry Page and Sergey Brin — began working on a research project they called Backrub. That, of course, was the project that resulted in Google. But also something more: it created the business model for the web. The deal that Google made with content creators was simple: let us copy your content for search, and we'll send you traffic.

For decades, the United States National Institute of Standards and Technology (NIST) has been guiding industry efforts through the many publications in its Computer Security Resource Center. NIST has played an especially important role in the adoption of Zero Trust architecture, through its series of publications that began with NIST SP 800-207: Zero Trust Architecture, released in 2020.

In mid-May 2025, Cloudflare blocked the largest DDoS attack ever recorded: a staggering 7.3 terabits per second (Tbps). This comes shortly after the publication of our DDoS threat report for 2025 Q1 on April 27, 2025, where we highlighted attacks reaching 6.5 Tbps and 4.8 billion packets per second (pps). The 7.3 Tbps attack is 12% larger than our previous record and 1 Tbps greater than a recent attack reported by cyber security reporter Brian Krebs at KrebsOnSecurity.

Today, we are excited to announce that Forrester has recognized Cloudflare Email Security as a Strong Performer and among the top three providers in the ‘current offering’ category in “The Forrester Wave: Email, Messaging, And Collaboration Security Solutions, Q2 2025” report. Get a complimentary copy of the report here. According to Forrester.

For the third consecutive year, Gartner has named Cloudflare in the Gartner Magic Quadrant for Security Service Edge (SSE) report. This analyst evaluation helps security and network leaders make informed choices about their long-term partners in digital transformation. We are excited to share that Cloudflare is one of only nine vendors recognized in this year’s report. You can read more about our position in the report here.

On April 11, 2025 09:20 UTC, Cloudflare was notified via its Bug Bounty Program of a request smuggling vulnerability (CVE-2025-4366) in the Pingora OSS framework discovered by a security researcher experimenting to find exploits using Cloudflare’s Content Delivery Network (CDN) free tier which serves some cached assets via Pingora.