2025-10-29
We identified and patched two DDoS vulnerabilities in our QUIC implementation related to packet acknowledgements. Cloudflare customers were not affected. We examine the "Optimistic ACK" attack vector and our solution, which dynamically skips packet numbers to validate client behavior. ...
2025-10-29
Many products at Cloudflare aren’t possible without pushing the limits of network hardware and software to deliver improved performance, increased efficiency, or novel capabilities such as soft-unicast, our method for sharing IP subnets across data centers. Happily, most people do not need to know the intricacies of how your operating system handles network and Internet access in general. Yes, even most people within Cloudflare. But sometimes we try to push well beyond the design intentions of Linux’s networking stack. This is a story about one of those attempts....
2025-10-29
Cloudflare mitigated a 12-hour DDoS attack against Moldova's Central Election Commission, blocking over 898 million malicious requests that peaked at 324,333 requests per second. This defense kept critical election infrastructure online and accessible for citizens during a critical parliamentary vote....
2025-10-28
Today over half of human-initiated traffic with Cloudflare is protected against harvest-now/decrypt-later with post-quantum encryption. What once was a cool science project, is the new security baseline for the Internet. We’re not done yet: in this blog post we’ll take measure where we are, what we expect for the coming years, and what you can do today....
2025-10-28
Cloudflare is launching an experiment with Chrome to evaluate fast, scalable, and quantum-ready Merkle Tree Certificates, all without degrading performance or changing WebPKI trust relationships....
2025-10-28
We present a data-driven framework to quantify cross-layer Internet resilience. We also share a list of measurements with which to quantify facets of Internet resilience for geographical areas....
2025-10-28
Cloudflare Workers' support for automatic tracing is now in open beta! Export traces to any OpenTelemetry-compatible provider for deeper application observability -- no code changes required...
2025-10-28
In Q3 2025, we observed Internet disruptions around the world resulting from government directed shutdowns, power outages, cable cuts, a cyberattack, an earthquake, a fire, and technical problems, as well as several with unexplained causes....
2025-10-27
The Internet is one big open system composed of many closed boxes — which makes measuring the Internet difficult. In this post we explore Internet measurement as a science....
2025-10-27
Cloudflare Radar has launched a new Top-Level Domain (TLD) page, providing insights into TLD popularity, traffic, and security. The top-ranking TLD may come as a surprise....
2025-10-27
While large cloud providers hold vast troves of passive network data, analyzing them is complicated. The scale, noise, and absence of definitive ground truth all create major hurdles. Yet by carefully quantifying these constraints and finding alternative forms of evidence, meaningful insights can still emerge....
2025-10-27
Cloudflare Radar has evolved significantly since its 2020 launch, offering deeper insights into Internet security, routing, and traffic with new tools and data that help anyone understand what's happening online....
2025-10-27
Coinciding with the ACM’s Internet Measurement Conference, the Cloudflare Research team is publishing a series of posts this week to share their research on building a more measurable, resilient, and transparent Internet. These posts will cover foundational concepts in Internet measurement, Internet resilience, cryptography, and networking. ...
2025-10-27
In this blog post we’ll discuss how Cloudflare thinks about measuring Internet quality, how our own Cloudflare speed test works, and our future plans for providing Internet measurement tools that help everyone build a better Internet....
2025-10-24
A recent npm supply chain attack compromised 18 popular packages. This post explains how Cloudflare’s graph-based machine learning model, which analyzes 3.5 billion scripts daily, was built to detect and block exactly this kind of threat automatically....
2025-10-24
Cloudflare is partnering with Visa and Mastercard to help secure the future of agentic commerce....
2025-10-21
This post explores the performance of BPF LPM tries, a critical data structure used for IP matching. ...
2025-10-17
Cloudflare Load Balancing now supports Monitor Groups, allowing you to combine multiple health monitors into a single, logical assessment. ...
2025-10-16
There's no way to audit a site’s client-side code as it changes, making it hard to trust sites that use cryptography. We preview a specification we co-authored that adds auditability to the web....
2025-10-14
Cloudflare investigated CPU performance benchmark results for Workers, uncovering and fixing issues in infrastructure, V8 garbage collection, and OpenNext optimizations. ...
