The Cloudflare Outage May Be a Security Roadmap

The Cloudflare Outage: A Security Roadmap for Organizations

In the early hours of November 18, Cloudflare, a leading provider of cloud-based security and performance services, experienced an intermittent outage that briefly knocked many of the internet's top destinations offline. While the outage was resolved within a few hours, its impact was felt far beyond the duration of the disruption. For organizations that rely on Cloudflare to block malicious traffic and protect their websites, the outage may have triggered an impromptu network penetration test, exposing vulnerabilities that were previously masked by the provider's services.

The Anatomy of the Outage

According to Cloudflare's postmortem, the disruption was triggered by a change to one of its database systems' permissions, which caused the database to output multiple entries into a "feature file" used by its Bot Management system. The larger-than-expected feature file was then propagated to all the machines that make up Cloudflare's network, causing the outage.

The Impact on Organizations

While the outage was brief, its impact was significant. Many organizations that rely on Cloudflare to block malicious traffic and protect their websites were forced to pivot away from the platform temporarily, exposing their infrastructure to potential threats. For some, this may have been the first time they realized the extent to which they relied on Cloudflare to protect their online presence.

The Importance of WAF Logs

Aaron Turner, a faculty member at IANS Research, noted that Cloudflare's Web Application Firewall (WAF) does a good job filtering out malicious traffic that matches any one of the top ten types of application-layer attacks. However, he also warned that organizations should take a closer look at their WAF logs during the outage to understand how their own app and website defenses may be failing without Cloudflare's help.

The Risk of Shadow IT

Nicole Scott, senior product marketing manager at Replica Cyber, called the outage "a free tabletop exercise, whether you meant to run one or not." She noted that the few-hour window was a live stress test of how organizations route around their own control plane and shadow IT blossoms under the time pressure. Scott advised organizations to ask themselves:

1. What was turned off or bypassed (WAF, bot protections, geo blocks), and for how long?
2. What emergency DNS or routing changes were made, and who approved them?
3. Did people shift work to personal devices, home Wi-Fi, or unsanctioned Software-as-a-Service providers to get around the outage?
4. Did anyone stand up new services, tunnels, or vendor accounts "just for now"?
5. Is there a plan to unwind those changes, or are they now permanent workarounds?
6. For the next incident, what's the intentional fallback plan, instead of decentralized improvisation?

The Need for Diversification

Martin Greenfield, CEO at Quod Orbis, noted that the outage was another reminder that many organizations may be putting too many of their eggs in one basket. He advised organizations to split their estate, spread WAF and DDoS protection across multiple zones, use multi-vendor DNS, segment applications so a single provider outage doesn't cascade, and continuously monitor controls to detect single-vendor dependency.

Conclusion

The Cloudflare outage may have been a brief disruption, but its impact will be felt for a long time. For organizations that rely on Cloudflare to protect their online presence, the outage may have triggered an impromptu network penetration test, exposing vulnerabilities that were previously masked by the provider's services. As organizations move forward, they must take a closer look at their WAF logs, assess their reliance on single-vendor solutions, and develop a plan to diversify their infrastructure and improve their security posture.

Source: https://krebsonsecurity.com/2025/11/the-cloudflare-outage-may-be-a-security-roadmap/