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Cloudflare Outage Traced to Internal Bug, Not a Cyberattack

Cloudflare has confirmed that the major service outage affecting a wide range of global platforms on Tuesday was not caused by a hacker attack

November 19, 2025

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Cloudflare Outage Traced to Internal Bug, Not a Cyberattack

Cloudflare has confirmed that the major service outage affecting a wide range of global platforms on Tuesday was not caused by a hacker attack, despite early speculation. The disruption impacted numerous high-traffic services — including ChatGPT, X, Shopify, Dropbox, and the widely played game League of Legends — and caused noticeable delays and access issues for organizations tied to critical infrastructure.

Initial Concerns and Early Indicators

When the incident began, Cloudflare reported a sudden “spike in unusual traffic,” prompting widespread concern that a cyberattack, possibly a distributed denial-of-service (DDoS) event, was underway. Given Cloudflare’s central role in safeguarding the internet from DDoS attacks, the possibility of Cloudflare itself coming under assault quickly drew attention.

Some users also noticed that government and transportation pages, such as New Jersey Transit, NYC Emergency Management, and France’s SNCF, experienced disruptions. This fueled speculation that a coordinated attack might be in progress.

Cloudflare’s Analysis: A Bug, Not an Attack

Cloudflare CTO Dane Knecht clarified the nature of the disruption, stating decisively that it was not related to any malicious activity. Instead, the outage stemmed from a latent software bug.

According to Knecht, a routine configuration update triggered a previously unnoticed flaw in a key component of Cloudflare’s bot-mitigation system. Once activated, the bug caused the underlying service to crash repeatedly, resulting in a cascading failure that spread across Cloudflare’s global network.

Knecht acknowledged the seriousness of the issue, stating:

“That issue, the impact it caused, and the time to resolution is unacceptable. Work is already underway to make sure it does not happen again.”

Timeline of the Incident

Based on Cloudflare’s status page:

  • 11:48 UTC — Cloudflare began investigating elevated error rates and widespread service impact.

  • 14:42 UTC — A fix was deployed, restoring most services.

  • Several hours later — Some residual errors were still being monitored.

Cloudflare says a detailed post-incident analysis will be published soon to explain the failure in depth and outline steps being taken to prevent similar issues.

Why the Attack Theory Was Plausible

Cloudflare is known for successfully mitigating some of the largest DDoS attacks ever recorded. As such, it would require extraordinary resources and technical capability for a threat actor to meaningfully disrupt Cloudflare’s own infrastructure.

However, high-visibility outages are often followed by false claims from hacktivists or opportunistic groups hoping to take credit, leading to initial confusion.

Conclusion

While the outage caused significant disruptions to major online services and critical organizations, Cloudflare has confirmed that it was not caused by a cyberattack. Instead, a software bug triggered by a routine update exposed a failure path within part of its security infrastructure. The company has pledged to strengthen internal safeguards and publish full details to support transparency and industry-wide learning.