Cloudflare reported a global service disruption on December 5, 2025 that briefly caused widespread HTTP 5xx errors across customer websites. The issue affected properties using Cloudflare network services before being resolved later that morning, according to official status updates and leadership communications.
Key Details
Reports from Search Engine Journal and user screenshots showed multiple prominent services returning 5xx errors through Cloudflare. Cloudflare's official status page (Cloudflarestatus.com) acknowledged active incidents and tracked remediation during the morning of December 5.
- Users accessing sites that rely on Cloudflare as a reverse proxy or CDN reported 5xx server errors, documented in coverage from Search Engine Journal.
- Screenshots highlighted outages on Claude.ai and Ahrefs.com, where Cloudflare-branded error pages appeared instead of normal site content.
- Cloudflare's status page recorded an incident affecting Workers scripts and the Workers KV namespace, initially marked as under investigation.
- At 4:12 a.m. ET, the status page reported that a fix had been applied and that Cloudflare was monitoring the situation.
- At 4:38 a.m. ET, Cloudflare said it was continuing to investigate Workers-related issues in the same public incident updates.
- By 6:06 a.m. ET, Cloudflare CTO Dane Knecht stated that the network issues affecting global traffic had been resolved and that sites using Cloudflare should be back online.
Background Context
Cloudflare operates a global network that provides content delivery, security, and DNS services for millions of internet properties. Many organizations route web traffic through Cloudflare's reverse proxy to improve performance and protect against attacks.
Cloudflare Workers is the company's serverless computing platform that runs JavaScript and other code at network edge locations. Workers KV is a key value storage service integrated with Workers for low-latency data access.
Search Engine Journal previously reported a significant Cloudflare outage earlier in the same month that also produced elevated 5xx errors. That earlier incident affected multiple online services using Cloudflare infrastructure.
HTTP 5xx status codes indicate server-side errors that prevent successful handling of client requests. When delivered through Cloudflare, such codes can originate either from origin servers or from Cloudflare infrastructure.
Source Citations
Information in this report draws from Cloudflare's public status communications and contemporaneous coverage from Search Engine Journal. Timing references and product names follow the wording from those sources.
- Cloudflarestatus.com for incident history and status updates.
- Search Engine Journal reporting on recent Cloudflare outages and resulting 5xx error spikes.
.svg)
.svg)
.svg)