Cloudflare outage on November 18, 2025 due to Bot Management error
On 18 November 2025, Cloudflare's network experienced a significant outage from 11:20 to 17:06 UTC, returning HTTP 5xx errors to users accessing customers' sites. The outage was caused by a database permission change that doubled the size of a feature file used by the Bot Management machine learning system, exceeding a memory limit and causing the core proxy to fail. Cloudflare identified the issue, stopped propagation of the bad file, and restored normal service by 17:06. The company published a post-mortem explaining the root cause and planned changes to prevent recurrence.
- Date it happened
- 2025-11-18
- Organisation involved
- Cloudflare
- Product, system or model
- Bot Management
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