Cloudflare Releases November 2025 Global Network Outage Report

Cloudflare released a post-incident report on the global network outage that occurred on November 18, 2025, confirming that the outage began at 11:20 UTC due to a chain reaction triggered by changes in database system permissions, rather than a cyberattack. Changes in ClickHouse database query behavior caused an abnormal increase in Bot Management System feature configuration files, exceeding memory allocation limits and triggering system crashes. The report documented the impact on core services such as the CDN during the outage and provided a timeline of the response. Cloudflare CEO Matthew Prince stated that this was the most severe outage since 2019 and pledged to take measures to prevent similar incidents in the future.