The library. Every incident, structured.

A growing archive of public postmortems, broken down into a consistent shape: what broke, why it cascaded, and what to take from it. New incidents added regularly.

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3 results · filtered
topic: waf
id
incident
org
date
duration
severity
tags
FM-026
The WAF Killswitch That Crashed the Older ProxyA global WAF testing-tool killswitch exposed an FL1 proxy bug, returning HTTP 500s for sites using the older proxy and Managed Ruleset.
Cloudflare
2025-12-05
25m
SEV-2
wafconfigproxy
FM-022
The Bot File That Crashed Cloudflare's ProxyA ClickHouse permissions change duplicated Bot Management feature rows, producing an oversized file that crashed Cloudflare proxy traffic paths.
Cloudflare
2025-11-18
5h 38m
SEV-1
configwafbot-management
FM-001
The Regex That Burned Every Cloudflare CPUA new managed WAF rule contained a regex that backtracked exponentially on live HTTP traffic, spiking CPU to nearly 100% across every edge server worldwide within seconds of deployment.
Cloudflare
2019-07-02
27m
SEV-1
wafregexcpu