Cloudflare Global Network incident

Resolved · Major outage · Started: November 18, 2025 at 8:45 AM · Resolved: November 18, 2025 at 4:01 PM

Updates

  1. Resolved · November 18, 2025 at 7:56 PM

    Post-mortem

    What happened

    The instability recorded this morning was caused by a global incident in the services of Cloudflare, the provider Cademí uses for DNS resolution. The failure affected companies and websites worldwide, as reported by outlets such as TecMundo, which noted that "an internal problem took down Cloudflare services, compromising access to many domains globally".

    During this period, some users had intermittent trouble accessing the platform, even though all of Cademí's infrastructure kept operating normally.

    Tecmundo: https://www.tecmundo.com.br/internet/408637-cloudflare-fora-do-ar-o-causou-a-queda-de-sites-no-mundo-todo.htm Financial Times: https://www.ft.com/content/9898e434-f7ec-4113-915b-fce28f1a9c25 Independent UK: https://www.independent.co.uk/tech/cloudflare-down-twitter-not-working-outage-b2867367.html

    Cause

    The incident started with a failure in Cloudflare's traffic resolution layer: an automatically generated configuration file used for traffic management and bot mitigation grew beyond its expected size, causing a failure in the system that acts as the DNS/Anycast gateway of Cloudflare's network. The collapse of this critical module prevented BGP/Anycast routes (Cloudflare's own global traffic distribution network) from propagating correctly and caused "500 Internal Server Error" responses or DNS resolution failures for dependent customers, which produced the intermittency we observed.

    Impact

    Intermittent access to the platform during the incident. No Cademí data, content or internal component was affected. The observed behavior was a direct consequence of the DNS provider's instability.

    It is worth remembering that Cloudflare is the most robust company in the world for this kind of solution, running one of the largest global DNS and traffic distribution networks on the internet. Incidents at this scale are extremely rare, but when they happen they immediately affect any service that depends on this layer. What we faced was a direct consequence of that global failure, not of any internal instability at Cademí.

  2. Resolved · November 18, 2025 at 4:01 PM

    Cloudflare's services have been restored and Cademí is now operating with continuous stability.

    Our team will keep watching the platform's behavior over the next hours to make sure everything is fully back to normal.

    In the next hours we will prepare and publish a detailed post-mortem, covering the root cause, impact and prevention actions.

    Thank you all for your patience and understanding. 🙏

  3. Monitoring · November 18, 2025 at 1:34 PM

    Cloudflare reports a gradual recovery of its services, and Cademí is already back to continuous, stable access.

    We keep closely monitoring the next developments to make sure everything keeps working normally. New updates will be posted if anything changes.

  4. Identified · November 18, 2025 at 11:15 AM

    Cloudflare's infrastructure is still unstable. We are following the resolution work at: https://www.cloudflarestatus.com/

  5. Identified · November 18, 2025 at 9:10 AM

    The system started showing intermittent availability, alternating between normal access and unavailability.

    We keep following it in real time and correlating the behavior with the ongoing Cloudflare incident. We will keep posting updates as new information comes in.

  6. Investigating · November 18, 2025 at 8:45 AM

    We have found that Cloudflare, the provider of our DNS layer, reported an incident that may affect multiple customers globally. We are monitoring closely and following all official updates: https://www.cloudflarestatus.com/