An early look at cryptographic watermarks for AI-generated content
Generative AI is reshaping many aspects of our lives, from how we work and learn, to how we play and interact. Given that it's Security Week, it's a good time to think about some of the unintended consequences of this information revolution and the role that we play in bringing them about.
Today's web is full of AI-generated content: text, code, images, audio, and video can all be generated by machines, normally based on a prompt from a human. Some models have become so sophisticated that distinguishing their artifacts — that is, the text, audio, and video they generate — from everything else can be quite difficult, even for machines themselves. This difficulty creates a number of challenges. On the one hand, those who train and deploy generative AI need to be able to identify AI-created artifacts they scrape from websites in order to avoid polluting their training data. On the other hand, the origin of these artifacts may be intentionally misrepresented, creating myriad problems for society writ large.
Part of the solution to this problem might be watermarking. The basic idea of watermarking is to modify the training process, the inference process, or both so that an artifact of Continue reading
Trapping misbehaving bots in an AI Labyrinth
Today, we’re excited to announce AI Labyrinth, a new mitigation approach that uses AI-generated content to slow down, confuse, and waste the resources of AI Crawlers and other bots that don’t respect “no crawl” directives. When you opt in, Cloudflare will automatically deploy an AI-generated set of linked pages when we detect inappropriate bot activity, without the need for customers to create any custom rules.
AI Labyrinth is available on an opt-in basis to all customers, including the Free plan.
AI-generated content has exploded, reportedly accounting for four of the top 20 Facebook posts last fall. Additionally, Medium estimates that 47% of all content on their platform is AI-generated. Like any newer tool it has both wonderful and malicious uses.
At the same time, we’ve also seen an explosion of new crawlers used by AI companies to scrape data for model training. AI Crawlers generate more than 50 billion requests to the Cloudflare network every day, or just under 1% of all web requests we see. While Cloudflare has several tools for identifying and blocking unauthorized AI crawling, we have found that blocking malicious bots can alert the attacker that you are Continue reading
Cloudflare for AI: supporting AI adoption at scale with a security-first approach
AI is transforming businesses — from automated agents performing background workflows, to improved search, to easier access and summarization of knowledge.
While we are still early in what is likely going to be a substantial shift in how the world operates, two things are clear: the Internet, and how we interact with it, will change, and the boundaries of security and data privacy have never been more difficult to trace, making security an important topic in this shift.
At Cloudflare, we have a mission to help build a better Internet. And while we can only speculate on what AI will bring in the future, its success will rely on it being reliable and safe to use.
Today, we are introducing Cloudflare for AI: a suite of tools aimed at helping businesses, developers, and content creators adopt, deploy, and secure AI technologies at scale safely.
Cloudflare for AI is not just a grouping of tools and features, some of which are new, but also a commitment to focus our future development work with AI in mind.
Let’s jump in to see what Cloudflare for AI can deliver for developers, security teams, and content creators…
If you Continue reading
Take control of public AI application security with Cloudflare’s Firewall for AI
Imagine building an LLM-powered assistant trained on your developer documentation and some internal guides to quickly help customers, reduce support workload, and improve user experience. Sounds great, right? But what if sensitive data, such as employee details or internal discussions, is included in the data used to train the LLM? Attackers could manipulate the assistant into exposing sensitive data or exploit it for social engineering attacks, where they deceive individuals or systems into revealing confidential details, or use it for targeted phishing attacks. Suddenly, your helpful AI tool turns into a serious security liability.
Today, as part of Security Week 2025, we’re announcing the open beta of Firewall for AI, first introduced during Security Week 2024. After talking with customers interested in protecting their LLM apps, this first beta release is focused on discovery and PII detection, and more features will follow in the future.
If you are already using Cloudflare application security, your LLM-powered applications are automatically discovered and protected, with no complex setup, no maintenance, and no extra integration needed.
Firewall for AI is an inline security solution that protects user-facing LLM-powered applications from Continue reading
Improved Bot Management flexibility and visibility with new high-precision heuristics
Within the Cloudflare Application Security team, every machine learning model we use is underpinned by a rich set of static rules that serve as a ground truth and a baseline comparison for how our models are performing. These are called heuristics. Our Bot Management heuristics engine has served as an important part of eight global machine learning (ML) models, but we needed a more expressive engine to increase our accuracy. In this post, we’ll review how we solved this by moving our heuristics to the Cloudflare Ruleset Engine. Not only did this provide the platform we needed to write more nuanced rules, it made our platform simpler and safer, and provided Bot Management customers more flexibility and visibility into their bot traffic.
In Cloudflare’s bot detection, we build heuristics from attributes like software library fingerprints, HTTP request characteristics, and internal threat intelligence. Heuristics serve three separate purposes for bot detection:
Bot identification: If traffic matches a heuristic, we can identify the traffic as definitely automated traffic (with a bot score of 1) without the need of a machine learning model.
Train ML models: When traffic matches our heuristics, we create labelled datasets Continue reading
Unleashing improved context for threat actor activity with our Cloudforce One threat events platform
Today, one of the greatest challenges that cyber defenders face is analyzing detection hits from indicator feeds, which provide metadata about specific indicators of compromise (IOCs), like IP addresses, ASNs, domains, URLs, and hashes. While indicator feeds have proliferated across the threat intelligence industry, most feeds contain no contextual information about why an indicator was placed on the feed. Another limitation of most feeds today is that they focus solely on blockable indicators and cannot easily accommodate more complex cases, such as a threat actor exploiting a CVE or an insider threat. Instead, this sort of complex threat intelligence is left for long form reporting. However, long-form reporting comes with its own challenges, such as the time required for writing and editing, which can lead to significant delays in releasing timely threat intelligence.
To help address these challenges, we are excited to launch our threat events platform for Cloudforce One customers. Every day, Cloudflare blocks billions of cyber threats. This new platform contains contextual data about the threats we monitor and mitigate on the Cloudflare network and is designed to empower security practitioners and decision makers with actionable insights from a global perspective.
On average, we process 71 Continue reading
One platform to manage your company’s predictive security posture with Cloudflare
In today’s fast-paced digital landscape, companies are managing an increasingly complex mix of environments — from SaaS applications and public cloud platforms to on-prem data centers and hybrid setups. This diverse infrastructure offers flexibility and scalability, but also opens up new attack surfaces.
To support both business continuity and security needs, “security must evolve from being reactive to predictive”. Maintaining a healthy security posture entails monitoring and strengthening your security defenses to identify risks, ensure compliance, and protect against evolving threats. With our newest capabilities, you can now use Cloudflare to achieve a healthy posture across your SaaS and web applications. This addresses any security team’s ultimate (daily) question: How well are our assets and documents protected?
A predictive security posture relies on the following key components:
Real-time discovery and inventory of all your assets and documents
Continuous asset-aware threat detection and risk assessment
Prioritised remediation suggestions to increase your protection
Today, we are sharing how we have built these key components across SaaS and web applications, and how you can use them to manage your business’s security posture.
Regardless of the applications you have connected to Cloudflare’s global network, Cloudflare actively scans Continue reading
Cloudflare enables native monitoring and forensics with Log Explorer and custom dashboards
In 2024, we announced Log Explorer, giving customers the ability to store and query their HTTP and security event logs natively within the Cloudflare network. Today, we are excited to announce that Log Explorer now supports logs from our Zero Trust product suite. In addition, customers can create custom dashboards to monitor suspicious or unusual activity.
Every day, Cloudflare detects and protects customers against billions of threats, including DDoS attacks, bots, web application exploits, and more. SOC analysts, who are charged with keeping their companies safe from the growing spectre of Internet threats, may want to investigate these threats to gain additional insights on attacker behavior and protect against future attacks. Log Explorer, by collecting logs from various Cloudflare products, provides a single starting point for investigations. As a result, analysts can avoid forwarding logs to other tools, maximizing productivity and minimizing costs. Further, analysts can monitor signals specific to their organizations using custom dashboards.
Log Explorer stores your Cloudflare logs for a 30-day retention period so that you can analyze them natively and in a single interface, within the Cloudflare Dashboard. Cloudflare log data is diverse, reflecting the breadth of capabilities Continue reading
Upgraded Turnstile Analytics enable deeper insights, faster investigations, and improved security
Attackers are increasingly using more sophisticated methods to not just brute force their way into your sites but also simulate real user behavior for targeted harmful activity like account takeovers, credential stuffing, fake account creation, content scraping, and fraudulent transactions. They are no longer trying to simply take your website down or gain access to it, but rather cause actual business harm. There is also the increasing complexity added by attackers rotating IP addresses, routing through proxies, and using VPNs. In this evolving security landscape, meaningful analytics matter. Many traditional CAPTCHA solutions provide simplistic pass or fail trends on challenges without insights into traffic patterns or behavior. Cloudflare Turnstile aims to equip you with more than just basic trends, so you can make informed decisions and stay ahead of the attackers.
We are excited to introduce a major upgrade to Turnstile Analytics. With these upgraded analytics, you can identify harder-to-detect bots faster, and fine-tune your bot security posture with less manual log analysis than before. Turnstile, our privacy-first CAPTCHA alternative, has been helping you protect your applications from automated abuse while ensuring a seamless experience for legitimate users. Now, using enhanced analytics, you can gain deeper insights into Continue reading
Extending Cloudflare Radar’s security insights with new DDoS, leaked credentials, and bots datasets
Security and attacks continues to be a very active environment, and the visibility that Cloudflare Radar provides on this dynamic landscape has evolved and expanded over time. To that end, during 2023’s Security Week, we launched our URL Scanner, which enables users to safely scan any URL to determine if it is safe to view or interact with. During 2024’s Security Week, we launched an Email Security page, which provides a unique perspective on the threats posed by malicious emails, spam volume, the adoption of email authentication methods like SPF, DMARC, and DKIM, and the use of IPv4/IPv6 and TLS by email servers. For Security Week 2025, we are adding several new DDoS-focused graphs, new insights into leaked credential trends, and a new Bots page to Cloudflare Radar. We are also taking this opportunity to refactor Radar’s Security & Attacks page, breaking it out into Application Layer and Network Layer sections.
Below, we review all of these changes and additions to Radar.
Since Cloudflare Radar launched in 2020, it has included both network layer (Layers 3 & 4) and application layer (Layer 7) attack traffic insights on a single Security & Attacks page. Over Continue reading
Conventional cryptography is under threat. Upgrade to post-quantum cryptography with Cloudflare Zero Trust
Quantum computers are actively being developed that will eventually have the ability to break the cryptography we rely on for securing modern communications. Recent breakthroughs in quantum computing have underscored the vulnerability of conventional cryptography to these attacks. Since 2017, Cloudflare has been at the forefront of developing, standardizing, and implementing post-quantum cryptography to withstand attacks by quantum computers.
Our mission is simple: we want every Cloudflare customer to have a clear path to quantum safety. Cloudflare recognizes the urgency, so we’re committed to managing the complex process of upgrading cryptographic algorithms, so that you don’t have to worry about it. We're not just talking about doing it. Over 35% of the non-bot HTTPS traffic that touches Cloudflare today is post-quantum secure.
The National Institute of Standards and Technology (NIST) also recognizes the urgency of this transition. On November 15, 2024, NIST made a landmark announcement by setting a timeline to phase out RSA and Elliptic Curve Cryptography (ECC), the conventional cryptographic algorithms that underpin nearly every part of the Internet today. According to NIST’s announcement, these algorithms will be deprecated by 2030 and completely disallowed by 2035.
At Cloudflare, we aren’t waiting until 2035 or even Continue reading
Advancing account security as part of Cloudflare’s commitment to CISA’s Secure by Design pledge
In May 2024, Cloudflare signed the Cybersecurity and Infrastructure Security Agency (CISA) Secure By Design pledge. Since then, Cloudflare has been working to enhance the security of our products, ensuring that users are better protected from evolving threats.
Today we are excited to talk about the improvements we have made towards goal number one in the pledge, which calls for increased multi-factor authentication (MFA) adoption. MFA takes many forms across the industry, from app-based and hardware key authentication, to email or SMS. Since signing the CISA pledge we have continued to iterate on our MFA options for users, and most recently added support for social logins with Apple and Google, building on the strong foundation that both of these partners offer their users with required MFA for most accounts. Since introducing social logins last year, about 25% of our users use it weekly, and it makes up a considerable portion of our MFA secured users. There’s much more to do in this space, and we are continuing to invest in more options to help secure your accounts.
According to the 2024 Verizon Data Breach Investigations Continue reading
Email Security now available for free for political parties and campaigns through Cloudflare for Campaigns
At Cloudflare, we believe that every political candidate — regardless of their affiliation — should be able to run their campaign without the constant worry of cyber attacks. Unfortunately, malicious actors, such as nation-states, financially motivated attackers, and hackers, are often looking to disrupt campaign operations and messaging. These threats have the potential to interfere with the democratic process, weaken public confidence, and cause operational challenges for campaigns of all scales.
In 2020, in partnership with the non-profit, non-partisan Defending Digital Campaigns (DDC), we launched Cloudflare for Campaigns to offer a free package of cybersecurity tools to political campaigns, especially smaller ones with limited resources. Since then, we have helped over 250 political campaigns and parties across the US, regardless of affiliation.
This is why we are excited to announce that we have extended our Cloudflare for Campaigns product suite to include Email Security, to secure email systems that are essential to safeguarding the integrity and success of a political campaign. By preventing phishing, spoofing, and other email threats, it helps protect candidates, staff, and supporters from cyberattacks that could compromise sensitive data.
Phishing attacks on political campaigns have been a Continue reading
Enhanced security and simplified controls with automated botnet protection, cipher suite selection, and URL Scanner updates
At Cloudflare, we are constantly innovating and launching new features and capabilities across our product portfolio. Today, we're releasing a number of new features aimed at improving the security tools available to our customers.
Automated security level: Cloudflare’s Security Level setting has been improved and no longer requires manual configuration. By integrating botnet data along with other request rate signals, all customers are protected from confirmed known malicious botnet traffic without any action required.
Cipher suite selection: You now have greater control over encryption settings via the Cloudflare dashboard, including specific cipher suite selection based on our client or compliance requirements.
Improved URL scanner: New features include bulk scanning, similarity search, location picker and more.
These updates are designed to give you more power and flexibility when managing online security, from proactive threat detection to granular control over encryption settings.
Cloudflare’s Security Level feature was designed to protect customer websites from malicious activity.
Available to all Cloudflare customers, including the free tier, it has always had very simple logic: if a connecting client IP address has shown malicious behavior across our network, issue a managed challenge. The system tracks malicious behavior Continue reading
Password reuse is rampant: nearly half of observed user logins are compromised
Accessing private content online, whether it's checking email or streaming your favorite show, almost always starts with a “login” step. Beneath this everyday task lies a widespread human mistake we still have not resolved: password reuse. Many users recycle passwords across multiple services, creating a ripple effect of risk when their credentials are leaked.
Based on Cloudflare's observed traffic between September - November 2024, 41% of successful logins across websites protected by Cloudflare involve compromised passwords. In this post, we’ll explore the widespread impact of password reuse, focusing on how it affects popular Content Management Systems (CMS), the behavior of bots versus humans in login attempts, and how attackers exploit stolen credentials to take over accounts at scale.
As part of our Application Security offering, we offer a free feature that checks if a password has been leaked in a known data breach of another service or application on the Internet. When we perform these checks, Cloudflare does not access or store plaintext end user passwords. We have built a privacy-preserving credential checking service that helps protect our users from compromised credentials. Passwords are hashed – i.e., converted into a random string of characters Continue reading
Chaos in Cloudflare’s Lisbon office: securing the Internet with wave motion
Over the years, Cloudflare has gained fame for many things, including our technical blog, but also as a tech company securing the Internet using lava lamps, a story that began as a research/science project almost 10 years ago. In March 2025, we added another layer to its legacy: a "wall of entropy" made of 50 wave machines in constant motion at our Lisbon office, the company's European HQ.
These wave machines are a new source of entropy, joining lava lamps in San Francisco, suspended rainbows in Austin, and double chaotic pendulums in London. The entropy they generate contributes to securing the Internet through LavaRand.
The new waves wall at Cloudflare’s Lisbon office sits beside the Radar Display of global Internet insights, with the 25th of April Bridge overlooking the Tagus River in the background.
It’s exciting to see waves in Portugal now playing a role in keeping the Internet secure, especially given Portugal’s deep maritime history.
The installation honors Portugal’s passion for the sea and exploration of the unknown, famously beginning over 600 years ago, in 1415, with pioneering vessels like caravels and naus/carracks, precursors to galleons and other ships. Portuguese sea exploration was driven by navigation schools Continue reading
How Cloudflare is using automation to tackle phishing head on
Phishing attacks have grown both in volume and in sophistication over recent years. Today’s threat isn’t just about sending out generic emails — bad actors are using advanced phishing techniques like 2 factor monster in the middle (MitM) attacks, QR codes to bypass detection rules, and using artificial intelligence (AI) to craft personalized and targeted phishing messages at scale. Industry organizations such as the Anti-Phishing Working Group (APWG) have shown that phishing incidents continue to climb year over year.
To combat both the increase in phishing attacks and the growing complexity, we have built advanced automation tooling to both detect and take action.
In the first half of 2024, Cloudflare resolved 37% of phishing reports using automated means, and the median time to take action on hosted phishing reports was 3.4 days. In the second half of 2024, after deployment of our new tooling, we were able to expand our automated systems to resolve 78% of phishing reports with a median time to take action on hosted phishing reports of under an hour.
In this post we dig into some of the details of how we implemented these improvements.
Welcome to Security Week 2025
The layer of security around today’s Internet is essential to safeguarding everything. From the way we shop online, engage with our communities, access critical healthcare resources, sustain the worldwide digital economy, and beyond. Our dependence on the Internet has led to cyber attacks that are bigger and more widespread than ever, worsening the so-called defender’s dilemma: attackers only need to succeed once, while defenders must succeed every time.
In the past year alone, we discovered and mitigated the largest DDoS attack ever recorded in the history of the Internet – three different times – underscoring the rapid and persistent efforts of threat actors. We helped safeguard the largest year of elections across the globe, with more than half the world’s population eligible to vote, all while witnessing geopolitical tensions and war reflected in the digital world.
2025 already promises to follow suit, with cyberattacks estimated to cost the global economy $10.5 trillion in 2025. As the rapid advancement of AI and emerging technologies increases, and as threat actors become more agile and creative, the security landscape continues to drastically evolve. Organizations now face a higher volume of attacks, and an influx of more complex threats that carry real-world consequences, Continue reading
Global expansion in Generative AI: a year of growth, newcomers, and attacks
AI (Artificial Intelligence) is a broad concept encompassing machines that simulate or duplicate human cognitive tasks, with Machine Learning (ML) serving as its data-driven engine. Both have existed for decades but gained fresh momentum when Generative AI, AI models that can create text, images, audio, code, and video, surged in popularity following the release of OpenAI’s ChatGPT in late 2022. In this blog post, we examine the most popular Generative AI services and how they evolved throughout 2024 and early 2025. We also try to answer questions like how much traffic growth these Generative AI websites have experienced from Cloudflare’s perspective, how much of that traffic was malicious, and other insights.
To accomplish this, we use aggregated data from our 1.1.1.1 DNS resolver to measure the popularity of specific Generative AI services. We typically do this for our Year in Review and now also on the DNS domain rankings page of Cloudflare Radar, where we aggregate related domains for each service and identify sites that provide services to users. For overall traffic growth and attack trends, we rely on aggregated data from the cohort of Generative AI customers that use Cloudflare for performance (including Continue reading
Dynamically optimize, clip, and resize video from any origin with Media Transformations
Today, we are thrilled to announce Media Transformations, a new service that brings the magic of Image Transformations to short-form video files wherever they are stored.
Since 2018, Cloudflare Stream has offered a managed video pipeline that empowers customers to serve rich video experiences at global scale easily, in multiple formats and quality levels. Sometimes, the greatest friction to getting started isn't even about video, but rather the thought of migrating all those files. Customers want a simpler solution that retains their current storage strategy to deliver small, optimized MP4 files. Now you can do that with Media Transformations.
For customers with a huge volume of short video, such as generative AI output, e-commerce product videos, social media clips, or short marketing content, uploading those assets to Stream is not always practical. Furthermore, Stream’s key features like adaptive bitrate encoding and HLS packaging offer diminishing returns on short content or small files.
Instead, content like this should be fetched from our customers' existing storage like R2 or S3 directly, optimized by Cloudflare quickly, and delivered efficiently as small MP4 files. Cloudflare Images customers reading this will note that this sounds just like their existing Image Transformation Continue reading