Cloudflare Outage Resolved: What Caused the Global Disruption Affecting X, ChatGPT, and More?

The disruption began abruptly, with users worldwide encountering Cloudflare error pages stating issues with proxy servers or internal errors. Cloudflare's status page first acknowledged the problem at around 12:03 UTC, describing an "internal service degradation" affecting multiple services, including widespread 500 errors, the dashboard, and API access.

Engineers quickly identified the issue and deployed fixes in phases. Key updates included restoring Cloudflare Access and WARP services, then broader application recovery. By 14:42 UTC, Cloudflare declared the incident resolved, with ongoing monitoring for any lingering effects. Full normalcy was reported within hours, including post-incident traffic spikes.

What Caused the Cloudflare Outage on November 18, 2025?

Cloudflare's official statement pinpointed the root cause as a configuration file automatically generated to handle threat intelligence and bot mitigation. This file exceeded expected size limits due to accumulated entries, leading to a crash in the underlying software layer responsible for processing traffic across several services.

A latent bug in the bot mitigation system was triggered by a routine configuration change, exacerbating the issue. Importantly, Cloudflare stressed this was an internal technical failure, not related to external attacks, unusual traffic spikes from malicious sources, or scheduled maintenance (though some datacenter work was ongoing in locations like Santiago).

This incident echoes past Cloudflare outages but was resolved faster than some historical events, thanks to rapid identification and rollback capabilities.

Sites and Services Impacted by the Cloudflare Outage

The outage rippled across the internet because Cloudflare acts as a reverse proxy, CDN, and security gateway for millions of domains. Downdetector recorded spikes in reports for numerous platforms:

• X (formerly Twitter)
• ChatGPT (OpenAI)
• Spotify
• Shopify
• Anthropic Claude
• League of Legends
• Zoom/Microsoft Teams
• Canva
• Others (e.g., Grindr, Indeed, Truth Social)

Even Downdetector itself was briefly inaccessible, underscoring the outage's scale.

On November 18, 2025, a significant portion of the internet ground to a halt when Cloudflare, one of the world's largest content delivery networks (CDNs) and security providers, suffered a global outage that lasted roughly three hours at its peak. Users attempting to access popular websites were greeted with cryptic error messages, such as "Error 500: Internal Server Error" or Cloudflare-specific proxy failures, leaving millions frustrated during morning hours in the Americas and business hours in Europe.

Cloudflare quickly mobilized, with its status page providing real-time updates that evolved from "investigating internal service degradation" to "fix implemented and incident resolved." By mid-morning ET, the company confirmed full recovery, but the event raised fresh questions about the fragility of centralized internet infrastructure. This deep dive explores the outage's timeline, root cause, widespread impact, Cloudflare's response, comparisons to past incidents, and critical lessons for businesses and users relying on such services.

Detailed Timeline of the November 18, 2025 Cloudflare Outage

• 11:20 UTC (6:20 a.m. ET): Initial spike in errors detected internally; unusual growth in a threat management config file begins triggering crashes.
• 12:03 UTC: Cloudflare publicly acknowledges the issue on cloudflarestatus.com, noting impacts to multiple customers including 500 errors and dashboard/API failures.
• 13:00-13:30 UTC: : Partial recoveries for services like Cloudflare Access and WARP; error rates drop to pre-incident levels for some components.
• 14:30 UTC: Fix fully deployed; Cloudflare declares the incident resolved, with monitoring for residual issues (e.g., dashboard login problems).
• Post-15:00 UTC: Services normalize completely, though natural traffic surges cause brief degradations.

Cloudflare CTO Dane Knecht posted a candid apology on X, stating the company "failed our customers and the broader Internet" and confirming it was not an attack.

Root Cause Analysis: Why Did the Cloudflare Outage Happen?

According to Cloudflare spokespeople and official statements reported across CNBC, Forbes, Reuters, and The Register, the outage stemmed from an internal software failure in a critical threat management system.

Specifically:

• An auto-generated configuration file, used to block malicious traffic and manage bot mitigation rules, ballooned beyond anticipated size.
• This oversized file caused a crash in the software handling traffic for bot detection, security challenges, and related services.
• A latent bug, activated by a routine config update, prevented proper handling of the file growth.

Cloudflare emphasized: "There is no evidence that this was the result of an attack or caused by malicious activity." This rules out DDoS attacks or cyberattacks, distinguishing it from threat-related incidents.

The failure affected the control plane rather than edge servers, meaning even fully operational origin servers couldn't serve traffic proxied through Cloudflare.