Changes / Klaviyo / Cloudflare incident disrupting onsite events
Klaviyo: Major incident: Cloudflare incident disrupting onsite events
Summary
Klaviyo reported a major Cloudflare-related outage: onsite forms appeared, but requests, events and subscriptions did not process; preference pages errored and API calls returned 403s. It started 2025-11-18 13:58 UTC and resolved 2025-11-18 19:06 UTC, lasting 5 h 7 min. Fixes were implemented, and all affected components were operational at resolution.
Machine-written from the diff below (Sol; type: incident outage). Check the diff before relying on it.
What changed
Before: not present
After: Cloudflare incident disrupting onsite events
Before: not present
After: major
Before: not present
After: resolved
Before: not present
After: 2025-11-18 13:58 UTC
Before: not present
After: 2025-11-18 19:06 UTC
Before: not present
After: Consent Pages, Klaviyo API, Lists, List Subscription, Server-side, Sign-up Forms, Signup Forms, Unsubscribe & Preference Pages
Before: not present
After: Cloudflare declared an incident around 6:30 am US Eastern causing all onsite activities, such as unsubscribe and subscribe preference pages and onsite form submissions to error out. Forms appear, but no requests or related events or subscriptions are processing. API calls are also experiencing 403s. https://www.cloudflarestatus.com/incidents/8gmgl950y3h7
We're currently investigating mitigation steps for the affected features.
Before: not present
After: Fixes have been implemented for some services and we are monitoring the issues.
Before: not present
After: This incident has been resolved, as of 2 pm US eastern. All affected components are operational.
First version of this incident archived by Rewindex. View the live incident (opens in new tab).
History of this incident
| When (UTC) | Change | Kind |
|---|---|---|
| Major incident: Cloudflare incident disrupting onsite events (this change) Klaviyo reported a major Cloudflare-related outage: onsite forms appeared, but requests, events and subscriptions did not process; preference pages errored and API calls returned 403s. It started 2025-11-18 13:58 UTC and resolved 2025-11-18 19:06 UTC, lasting 5 h 7 min. Fixes were implemented, and all affected components were operational at resolution. | Major incident |