* This post was updated at 11:45 a.m. Pacific time to clarify that the use case described here is a proof of concept and a personal project. Some sections have been updated for clarity. Matrix is the gold standard for decentralized, end-to-end encrypted communication. It powers government messaging systems, open-source communities, and privacy-focused organizations worldwide. […]
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RSS feed for this sectionRoute leak incident on January 22, 2026
On January 22, 2026, an automated routing policy configuration error caused us to leak some Border Gateway Protocol (BGP) prefixes unintentionally from a router at our data center in Miami, Florida. While the route leak caused some impact to Cloudflare customers, multiple external parties were also affected because their traffic was accidentally funnelled through our […]
How we mitigated a vulnerability in Cloudflare’s ACME validation logic
This post was updated on January 20, 2026. On October 13, 2025, security researchers from FearsOff identified and reported a vulnerability in Cloudflare’s ACME (Automatic Certificate Management Environment) validation logic that disabled some of the WAF features on specific ACME-related paths. The vulnerability was reported and validated through Cloudflare’s bug bounty program. The vulnerability was […]
Astro is joining Cloudflare
The Astro Technology Company, creators of the Astro web framework, is joining Cloudflare. Astro is the web framework for building fast, content-driven websites. Over the past few years, we’ve seen an incredibly diverse range of developers and companies use Astro to build for the web. This ranges from established brands like Porsche and IKEA, to […]
Malware Intercepts Googlebot via IP-Verified Conditional Logic
Some attackers are increasingly moving away from simple redirects in favor of more “selective” methods of payload delivery. This approach filters out regular human visitors, allowing attackers to serve malicious content to search engine crawlers while remaining invisible to the website owner. What did we find? During a malware investigation, we identified a selective content […]
Google Sees Spam, You See Your Site: A Cloaked SEO Spam Attack
We recently handled a case where a customer reported strange SEO behavior on their website. Regular visitors saw a normal site. No popups. No redirects. No visible spam. However, when they checked their site on Google, the search results were flooded with eBay-type-looking websites and “Situs Toto” gambling spam. This is a professional-grade SEO cloaking […]
Fake Browser Updates Targeting WordPress Administrators via Malicious Plugin
We recently investigated a case involving a WordPress website where a customer reported persistent fake pop-up notifications appearing on their site. The warnings were urging them to update their browser (Chrome or Firefox), even though their software was already fully up-to-date. What made this case particularly unique was the targeting. The fake alerts were not […]
Vulnerability & Patch Roundup — December 2025
Vulnerability reports and responsible disclosures are essential for website security awareness and education. Automated attacks targeting known software vulnerabilities are one of the leading causes of website compromises. To help educate website owners about potential threats to their environments, we’ve compiled a list of important security updates and vulnerability patches for the WordPress ecosystem this […]
Code Orange: Fail Small — our resilience plan following recent incidents
On November 18, 2025, Cloudflare’s network experienced significant failures to deliver network traffic for approximately two hours and ten minutes. Nearly three weeks later, on December 5, 2025, our network again failed to serve traffic for 28% of applications behind our network for about 25 minutes. We published detailed post-mortem blog posts following both incidents, […]
Innovating to address streaming abuse — and our latest transparency report
Cloudflare’s latest transparency report — covering the first half of 2025 — is now live. As part of our commitment to transparency, Cloudflare publishes such reports twice a year, describing how we handle legal requests for customer information and reports of abuse of our services. Although we’ve been publishing these reports for over 10 years, […]
