Cloudflare Outage Disrupts Internet Access Globally

On November 18, 2025, Cloudflare, a prominent U.S. internet infrastructure company, experienced a significant global outage that disrupted access to numerous websites. The incident began at 11:48 AM London time, leading to error messages appearing across various platforms, including major sites like X and OpenAI. By 2:48 PM, Cloudflare announced that a fix had been implemented and that they were monitoring the situation to ensure services returned to normal.

The Guardian

The outage was attributed to a malfunction in a configuration file that is automatically generated to manage threat traffic. This file exceeded its expected size, causing a crash in the software system responsible for handling traffic for several of Cloudflare's services. Cloudflare clarified that there was no evidence suggesting the outage resulted from a malicious attack. During the troubleshooting process, the company disabled an encryption service called Warp in London, which affected users attempting to connect to the internet through that service.

The Guardian

Cloudflare's spokesperson issued an apology to customers and the broader internet community, stating, “We will learn from today’s incident and improve.” The company emphasized its commitment to resolving the issues and restoring normal operations as quickly as possible. Following the incident, Cloudflare expected some services to experience brief degradation due to increased traffic as users returned to the affected sites.

The Guardian

Professor Alan Woodward from the Surrey Centre for Cyber Security highlighted the critical role of companies like Cloudflare in the internet's infrastructure. He noted, “We’re seeing how few of these companies there are in the infrastructure of the internet, so that when one of them fails it becomes really obvious quickly.” This statement underscores the vulnerability of the internet's backbone, where the failure of a single entity can have widespread repercussions.

The Guardian

The Cloudflare outage raises concerns about the reliability of internet infrastructure, especially given that it follows a recent outage of Amazon Web Services, which similarly affected thousands of websites. As the internet becomes increasingly reliant on a limited number of service providers, the potential for significant disruptions grows, prompting discussions about the need for diversification and resilience in internet infrastructure.

The Guardian

While Cloudflare has stated that the outage was not caused by malicious activity, the lack of detailed information about the specific nature of the configuration file issue leaves some questions unanswered. Additionally, the timeline of the outage and the exact number of affected sites remains unclear, with various reports indicating differing levels of impact across the internet.

The Guardian

• “We will learn from today’s incident and improve.” — Cloudflare Spokesperson

The Guardian

• “To be clear, there is no evidence that this was the result of an attack or caused by malicious activity,” — Cloudflare Spokesperson

The Guardian

• “We’re seeing how few of these companies there are in the infrastructure of the internet, so that when one of them fails it becomes really obvious quickly,” — Prof. Alan Woodward, Surrey Centre for Cyber Security

The Guardian