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Category Archives for "CloudFlare"

Origin Range Requests: Serving large files without range-request tuning

A video player seeking to the middle of a movie asks for a few megabytes. Under our old range caching, that one request could make Cloudflare pull 128 MiB from the origin and move it between data centers, sometimes after the viewer had already left. Range requests are how large files get delivered, and caching them naively easily leads to wasted network bandwidth and wasted disk operations when running a CDN at scale.

So we rebuilt how our cache handles them. For R2, Cloudflare's object storage, p99 time to first byte dropped by about half, and a follow-up improvement cut tiered cache traffic for R2 and similar workloads by about 6%.

Today, we're making that new implementation available as Origin Range Requests, a self-service feature on all plans. There's no range size to tune and no need to contact support. Turn it on with a Cache Rule, and Cloudflare handles the rest.

A request for part of a file

An HTTP range request asks for part of a resource instead of the whole resource. The client sends a normal GET with a Range header:

GET /movie.mp4 HTTP/1.1
Host: example.com
Range: bytes=1048576-2097151

If the server supports the Continue reading

Bringing post-quantum cryptography to geographically fenced key management

Today, Cloudflare is launching a post-quantum geographically restricted key manager in support of our Data Localization Suite (DLS) in closed beta. This new PQ GeoKey Manager is a cornerstone of Cloudflare’s data sovereignty solutions, making sure that a customer's decryption keys are only accessible in their chosen geography. GeoKey Manager implements this by wrapping each decryption key such that it can only be decrypted by Cloudflare servers that are located in the allowed geography.

While general availability (GA) is planned for Q1 2027, today’s launch is an important milestone on our journey to support our customers’ data sovereignty goals while also migrating all Cloudflare products to post-quantum (PQ) cryptography.

Governments, financial institutions, healthcare providers, and defense organizations process highly sensitive data that can remain sensitive for years or decades after it is produced. Encryption is often required to protect this data. When classical, public-key encryption is used, adversaries do not immediately need a quantum computer today to put that data at risk: they can store the ciphertext and retain them until quantum computers can break the public key cryptography protecting it — an attack strategy known as harvest now, decrypt later.

For organizations with geographic requirements, resisting that threat is Continue reading

Localizing compliance at scale: achieving South Korea’s ISMS certification

For ten days, auditors appointed by the Korea Internet & Security Agency (KISA) sat together with us and worked through 80 controls. That is what it took for a company headquartered in the United States, operating a global network serving Korean users, to be certified in South Korea. Cloudflare has now obtained South Korea's Information Security Management System (ISMS) certification under the ISMS-P framework.

For customers in Korea, this is more than a compliance checkbox. It is evidence that Cloudflare's security and privacy program has been examined not only for whether our controls exist, but for how they operate in the context of Korean law, the Korean language, and the particular expectations of Korean regulators.

What a Korean user sees when they sign up

The most visible result of this work is the Cloudflare account sign-up page. In most parts of the world, the line that sits above the sign-up button reads: "By continuing, I agree to Cloudflare's terms, privacy policy, and cookie policy."

A user signing up from South Korea sees something different. The Korean experience is triggered by the country selected at sign-up and by IP geolocation from within South Korea, and it breaks the same Continue reading

Introducing full transaction detection for Cloudflare WAF

Today, we are expanding our web application firewall (WAF) by adding two new capabilities: full transaction detections and response rules. Full transaction detections evaluate each HTTP request alongside its response to identify evidence of exploitation. It helps answer both "Does this request look malicious?" and "What happened when the application handled it?" Response rules can then block the origin’s response before it reaches the requester.

These are valuable protections because the latest frontier models are uncovering vulnerabilities buried deep in widely used software, giving defenders clarity on what to fix — and attackers new paths to exploit. The recent php2shell vulnerability shows the stakes: a flaw in a common software component can put applications across the Internet at risk. AI agents scanning for vulnerabilities can be extremely persistent, adapting payloads using feedback, and chaining vulnerabilities, credentials, and permissions. An application's response can reveal whether an attempt worked and give an attacker information that helps them go deeper.

Inspecting incoming requests remains essential for stopping recognizable attacks before they reach an application. But some threats become clear only when the request is considered alongside what the origin returns. A suspicious input followed by a response exposing sensitive information tells Continue reading

Cloudflare deploys protections against php2shell vulnerability

Today, Calif.io, Wiz, OpenAI and Quarkslab disclosed two vulnerabilities in PHP, tracked as CVE-2026-109618 and CVE-2026-109619 and known as php2shell. The vulnerabilities affect all web servers running PHP 5.4 or later and they may allow an attacker to cause denial of service, remote code execution, and data exposure when an application processes specially crafted HTTP traffic.

Cloudflare has been part of a coordinated effort to deploy mitigations to protect the Internet, working with PHP foundation, OpenAI and Wiz among others. Cloudflare has developed and deployed web application firewall (WAF) protections since early October 2026, which were deployed about 9 hours ahead of public disclosure. Starting on October 21 3:02 am UTC, Cloudflare customers using our free or paid WAF were protected by default against php2shell.

Cloudflare successfully deployed multiple mitigations for all its customers while the vulnerability was leaked before the official release date and we observed attack traffic targeting our customers. We observed how attackers were mutating the attack payload to try to bypass our protections by tracking the volume of matches and cross-referencing with the rule logic.

Protecting against php2shell required more than standard request-based rules. Request data alone does not always provide enough evidence to distinguish an Continue reading

How Commerce.com and Cloudflare are getting storefronts ready for AI agents

AI can write code and pass the bar exam, but it still struggles to buy a pair of shoes online.

That’s because websites were built for humans, not agents. Most agents that shop for someone today work from a site’s HTML — they look at the page, guess which button does what, click, and try again when they get it wrong. This process is slow, uses a lot of tokens, and something as seemingly innocuous as a theme change can break it.

Enter WebMCP: a browser standard from Google that gives AI agents structured tools on a page, like search_products. Instead of hunting for buttons, the agent calls the exact tool it needs directly, making shopping faster, cheaper, and far more reliable. Because WebMCP is still an experimental proposed browser standard in early preview, it’s currently available behind experimental Chrome flags (chrome://flags/#enable-webmcp-testing), in Chrome Origin Trials, in some agentic browsers, and across developer environments like Cloudflare Kitesurf.

In August, we launched edge implementation of WebMCP in beta. Turn it on, and Cloudflare injects a tiny script at the edge to make those tools available automatically, without site owners writing a single line of code.

Commerce.com, a Continue reading

8 eMudhra certificates are compromised. Here’s what you need to know

On October 19, 2026, at approximately 17:00 UTC, Cloudflare became aware that private keys associated with eight eMudhra intermediate certificates were compromised. These certificates were widely trusted by browsers, operating systems, and also within Cloudflare. Because the keys themselves are weak, an attacker can create a forged certificate for any domain and use it to impersonate servers to intercept or modify traffic. This is a serious security incident with implications across the Internet. For reference, here is a link to more information about how SSL certificates work and why they are so critical to the operation of the Internet.

We immediately prioritized patching critical services across Cloudflare to protect our customers ahead of the public disclosure of the vulnerability. Our security review has not identified active exploitation of this issue on Cloudflare services.

We have released updates for the Cloudflare One Clients, also known as WARP or the 1.1.1.1 app, and Cloudflare Tunnel, also known as cloudflared. We have also deployed mitigations across our CDN, Developer, and Zero Trust products. If you are using Cloudflare Zero Trust with Gateway and an up-to-date client (see below), you are automatically protected.

Our response

We prioritized updating services that use public certificates Continue reading

Introducing tsrs: A port of TypeScript to Rust

Cloudflare and VoidZero are now working with Max Schwenk of Owner.com on tsrs, a Rust port of the TypeScript compiler. We are doing this work in close collaboration with the TypeScript team, and incubating tsrs as part of the Oxc JavaScript compiler toolchain.

Our goal is to help developers spend less time waiting for their code to be checked and more time building. Making TypeScript faster and more memory-efficient also helps bring complete development environments to more places, including right in your browser.

To be clear, we are not forking TypeScript. We believe the TypeScript team should remain in full control of the language’s design and direction. They have maintained a long-term vision while guiding TypeScript’s adoption across the JavaScript community. We do not want to change that.

The TypeScript team can move quite fast on many things, but for some features they may spend years intentionally exploring options and making prototypes before picking the right implementation. A Rust port has to follow those decisions closely, or it will eventually fall apart and become incompatible. We have to preserve the TypeScript language strictly based on its original implementation – and the TypeScript team should remain solely responsible for Continue reading

Cutting our inference bill by 68% by being obsessive about optimization

When we previously blogged about our AI code reviewer in April, an average review cost a palatable $1.19. By the end of August, that figure had shot up to about $2.46. We hadn't made any significant architectural changes: the coordinator was still handing work to the same set of specialist reviewers, and the same risk tiers decided how intensive of a review we gave.

Around mid-September we tasked our agents with working out where those tokens were going and cutting them — aggressively. With code quality at high effort, the average review now costs just $0.77, down 68% from the $2.43 it averaged over our two most expensive weeks before we started. Our main goal was to cut costs, but as part of this work we also managed to optimize the reviewer, so that the median review now takes just 1m 32s instead of the 4m 09s it took before.

About 40% of the savings came from changes and optimizations to the reviewer's code, and the rest from experimenting with which models we use and how much effort they put in.

How a review doubled in cost

The chart below shows the cost of an Continue reading

Introducing Clairic, a new System One class of extraction models

Today, we're announcing a preview of a new class of System One-style models: extraction models. Our first one, Clairic, is available hosted on Workers AI as @cf/cloudflare/clairic.We intend to release the model open-weights soon. Clairic is an extraction model that is able to extract, compute, estimate, and forecast values from unstructured inputs — all at a significantly higher accuracy, faster latency, and cheaper cost than traditional LLMs.

Context

When System One models were announced by TypeSafe a month ago, it took the industry by storm. As referenced by TypeSafe in their blog and defined by Daniel Kahneman’s book Thinking, Fast and Slow, a System One model should be fast and precise, which contrasts a System Two model that is capable of deliberate reasoning (like LLMs). With this, TypeSafe introduced Jev — a model that is purpose-fit for a specific use case, and priced accessibly given its niche domain. It excelled where LLMs failed, helping users make decisions based on probabilities and well-typed outputs. The introduction of Jev prompted people to start thinking about a new class of models that were not LLMs and how to integrate them into their workflows.

We were inspired by the concept of System One models and Continue reading

Beyond the patch: Protecting your NetScaler gateway against future vulnerabilities

The recent disclosure of a major vulnerability in Citrix NetScaler pointed to a widespread weak point: a login page is an attack surface that can be used to compromise and access an application server. Indeed, the disclosures included an actively exploited flaw that allowed attackers to execute commands on affected gateways without signing in. As with any emergency patch, admins had to weigh cutting off or disrupting their users’ access with the risk of delaying a critical security update.

If you’re a NetScaler customer and you haven’t patched your instance, stop reading and go do that. This was a bad one. Once you’ve finished the patch, we’ll explore how to avoid a future fire drill by laying additional security controls.

This issue extends beyond NetScaler and can be applied to any internal application available on the Internet. Remote desktop portals, administrative consoles, and other publicly accessible authentication pages all deserve the same scrutiny: Does the intended audience require unrestricted Internet reachability? And can an attacker bypass this authentication check to reach the application's server?

Citrix released software updates to address the flaw, and Cloudflare followed with an emergency web application firewall (WAF) rule on October 1. But having a patch available Continue reading

Continuous accountability for Verified bots

A driver’s license tells you who someone is and that they passed a driving test, not whether they’ll drive responsibly in the future. The same is true for bots: verifying who operates it creates accountability, but trust depends on what it does next. A known bot can still ignore website preferences, overwhelm origins, or evade controls. It’s not always malicious — often it’s just a misconfiguration or a bug.

As we described in a previous blog post on bot behavior, we strive to verify two questions: “Are you who you say you are?” and “Can we trust you?” To be a Cloudflare Verified Bot, you broadly need to meet three criteria:

  1. Identify yourself accurately and securely
  2. Do only what you say you will do
  3. Don’t engage in abusive behavior

Bots use Web Bot Auth to sign requests that establish their identity, which BotBase then catalogues in an open format. With identification addressed, our focus shifts to the second cardinal rule of Verified bots: thou shalt do no harm.

Today we introduce a system to evaluate and report when Verified bot behavior starts to deviate from this rule, ensuring that the answer to “Can we trust you?” remains “Yes.”

Continue reading

A fully programmable secure web gateway

Every secure web gateway on the market works the same way: traffic matches a condition. A terminal action fires. Allow, Block, Isolate, Log. This model has been the foundation of network security for nearly 30 years, and it handles the common case well. But it has a ceiling, and customers with complex environments hit that ceiling regularly.

Earlier this year, we shared our vision to build a truly programmable SASE platform. We also outlined how the term programmability has become diluted by the security industry. Most vendors claim programmability because they have public APIs, Terraform providers, webhooks, and alerting. Cloudflare offers all of those things too, but that’s not enough. True programmability means running your own code — arbitrary logic that you wrote for your specific environment — inline in the policy evaluation path, at the moment a security decision is made.

Today, we’re excited to announce Cloudflare is bringing true programmability to Cloudflare Gateway and DLP (Data Loss Prevention) by integrating it with the entirety of our edge computing platform. We are releasing a new type of Gateway action, Forward, and custom validation functions, available to all Zero Trust plans. These capabilities allow you to use a Cloudflare Worker Continue reading

Deploy with Void

VoidZero's tools such as Vite, Vitest, Oxc, and Rolldown — bundled in one toolchain as Vite+ — have made frontend development faster, but building full-stack applications requires more than just a tooling stack. These applications need server routes, databases, local development environments, and a fast and easy way to deploy ideas to production.

We’re excited to open-source three new products that bring server routing, typed data access, and Cloudflare deployment into a unified Vite workflow.

  • Void Platform: A shared deployment platform for teams to host Void apps on Cloudflare.
  • Void SDK: A composable JavaScript SDK for building full-stack apps with Vite.
  • Void CLI: A CLI for provisioning resources and deploying Vite apps to Cloudflare.

The CLI deploys apps built with the SDK to the Platform. All three products are open-sourced as a single JavaScript package and Vite plugin that you can install via npm install void. With Void, you can build your server and client together, carry types from your database to the UI, and let Void automatically provision the Cloudflare resources that your app uses.

We originally set out to build a single, private platform for all users to deploy apps to. After VoidZero joined Cloudflare, we Continue reading

Cloudflare and OpenAI: Making AI discovery better for everyone

Optimizing your site for AI is of little use if AI can't find it. The answer to someone's question may already be on your website: the installation guide you spent a week writing, or a first-hand account of using a product, with the details that make the difference for whether they buy it. As more people turn to AI for help, you want those systems to find your work, represent it accurately, and send interested people your way. You also want control over how they access your site.

Cloudflare and OpenAI launched a research pilot in July 2026 with those interests in mind. We wanted to find out whether signals from Cloudflare’s network could help ChatGPT users discover new content more efficiently.

Today, we’re sharing early results. So far, the answer is a resounding yes: the pilot has brought previously unknown pages into OpenAI’s search index, giving ChatGPT more sources to draw on to help people find relevant, timely information. Along the way, we’ve learned more about what makes a page worth discovering and how AI systems use the web.

Finding more of the web

The web is full of specifics. Someone fixing a washing machine needs the manual for Continue reading

Yandex outage: Data shows that instead of going dark, malicious bots went on the move

Following reported strikes on Yandex data centers, claims circulated on the Internet that Russian bot farms and influence operations had been knocked offline. HTTP traffic charts showed steep drops, fueling speculation that the infrastructure damage had stopped these malicious actors. However, aggregate traffic metrics can easily mislead. There are two autonomous system numbers (ASNs) associated with Yandex: AS13238 is used by Yandex’s search engine, while AS200350 runs its cloud services.

Using Cloudflare Radar and Bot Management data, we analyzed how these two ASNs were affected — and while both saw drops in traffic, they saw differing impact.

  • Yandex Search (AS13238): The drop in traffic consisted almost entirely of verified search crawlers indexing web pages, images, and site resources.
  • Yandex.Cloud (AS200350): There was a decline in malicious activities like vulnerability scanning and probing, but high-volume automation did not vanish — it simply migrated to other hosting providers.

While malicious traffic may originate from a particular provider, it does not necessarily tell us who is responsible for the traffic. Understanding why the strikes had little lasting effect on malicious traffic requires analyzing request behavior, rather than just overall traffic patterns.

What happened: the effect of the strikes and pre-event Continue reading

Inside Hyperdrive: How we solved a rare Hyperdrive MySQL caching bug

Hyperdrive support for MySQL is now generally available (GA). Hyperdrive, Cloudflare’s database connection pooler for Workers, initially only supported Postgres. Since we announced the beta for MySQL protocol support last year, we have been working on making our MySQL handling as reliable as our Postgres support.

We’ve learned some things from building and running a MySQL connection pooler on Cloudflare’s network. It turns out that the difference between beta and GA is just 20 bug fixes in a trenchcoat.

During the beta, our goal was to validate that real-world customer usage hit our production availability target of 99.99%. We knew there were gaps in our reliability since we track how often client connections from a Worker end in an error related to Hyperdrive. In addition, we had feedback from customers in the beta that led to the discovery of a rare and subtle bug in our production environment. To convey the complexity of this particular bug, we first need to explain how Hyperdrive works.

What is Hyperdrive?

Hyperdrive is a distributed database connection pooler that connects Cloudflare Workers to SQL databases. Hyperdrive holds warm SQL connections open on our global network and shares these connections across many Worker requests. Continue reading

Under the hood, off the hot path: How D1 scales to millions of databases

Traditional database architecture assumes you have one or two big database clusters per application, usually accompanied by a connection pooling solution. AI-assisted development and vibe coding platforms turn this model inside out and are driving applications toward many small databases: one per user, application, preview environment, or tenant.

That model fits D1 particularly well. D1 is Cloudflare's managed, serverless database based on SQLite. It allows you to create millions of databases and only pay for what you use.

The question becomes: how do you scale the control plane for millions of databases without making every query slower by sending it through centralized bottlenecks?

We made a lot of architectural changes to scale out D1 to support platforms with millions of created databases, hundreds of thousands of which are active at any point.

This post is a behind-the-scenes deep dive into how the D1 control plane works. Many of the architectural patterns we will describe can be used by anyone building on top of Cloudflare’s Developer Platform. The post also gives a glimpse into how we build our own control planes.

Growth in numbers

There was already a steady growth in D1 usage when we started planning these changes, but we Continue reading

Rewinding the exponential: How we keep hardware usage down

More than 20% of the web sits behind Cloudflare’s network, and our team, the Data team, owns the data pipeline responsible for plumbing that data (and more) from our global network to applicable central data centers. The Cloudflare network is a globally distributed system supporting tens of thousands of servers. Data that power Cloudflare Logs, SQL API, observability, internal analytics, and more flow through this network and use our data pipeline to serve customers.

In May of this year, we were providing data delivery at roughly two billion events per second. This includes customer traffic as well as data sent from internal teams. Year after year, we tackle the same problem — exponential traffic growth against linear hardware growth. We have to react to this increase in order to keep resource costs under control. Over the past five years, we’ve made various improvements to compensate for the data volume increase in comparison to hardware allocation, equivalent to deferring two and a half years of hardware expansion. This post details those changes: breaking up our monolithic data schema in 2022, adjusting compression in 2024, rearchitecting pipeline replication in spring 2026, decentralizing sampling in summer 2026, and introducing aggregations into the Continue reading

Filter, reshape, and redact logs before export with Transformers

Logpush delivers logs in batches as quickly as possible, enabling Cloudflare to provide information almost in real time. During our recent Birthday Week, we made Logpush available on all self-serve plans and Transformers generally available.

Those changes were among eight major updates to Cloudflare Observability and reflect our commitment to make every Cloudflare feature available to everyone. This post takes a deeper look at how Transformers work inside Logpush's export pipeline. Observability teams use Logpush to export Cloudflare logs to security information and event management systems (SIEMs), analytics platforms, and object storage. Before those logs reach their destination, teams may need to remove health checks, omit sensitive fields, or reshape records for dashboards and investigations. Today, this often requires a separate processing service that teams must deploy, scale, monitor, and maintain.

For example, a team that collects logs from multiple CDNs can add a static provider field to normalize records before they reach its analytics platform. Teams also pay to export, ingest, and store records they discard as soon as they arrive, so filtering them before delivery can reduce downstream data volume and cost.

With Transformers, that processing moves into the Logpush export workflow.Teams define a SQL query Continue reading

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