Cloudflare outage on November 18, 2025
Nov 18, 2025Matthew Prince
Summary
This post details a major outage on November 18, 2025, caused by a database permission change that led to an oversized Bot Management feature file. This file's size exceeded the software's limit, causing widespread failures in core CDN, security services, Turnstile, Workers KV, and Access. The incident highlighted issues with database query behavior, feature file propagation, and the impact of configuration file size limits on network stability. It also led to a temporary failure of the status page and initial misdiagnosis as a DDoS attack. The post outlines the resolution steps and commits to preventing future occurrences.
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