# Klaviyo: Cloudflare incident disrupting onsite events

- Impact (vendor’s label): major
- Status: resolved
- Started: 2025-11-18 13:58 UTC · Resolved: 2025-11-18 19:06 UTC · Duration: 5.1 h
- Updates: 3 · Affected components: Consent Pages, Unsubscribe & Preference Pages, Sign-up Forms, Signup Forms, Lists, List Subscription, Klaviyo API, Server-side
- [Vendor status page: https://stspg.io/k0fc5ckvcp0f](https://stspg.io/k0fc5ckvcp0f)
- [Company: Klaviyo](https://rewindex.com/company/klaviyo.md)

## 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, sol)_
## Timeline of updates

- **identified** 2025-11-18 13:58 UTC: 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.
- **monitoring** 2025-11-18 14:34 UTC: Fixes have been implemented for some services and we are monitoring the issues.
- **resolved** 2025-11-18 19:06 UTC: This incident has been resolved, as of 2 pm US eastern. All affected components are operational.

## Rewindex changes for this incident

- 2025-11-18 13:58 UTC: [Major incident: Cloudflare incident disrupting onsite events](https://rewindex.com/change/idf7424142696f8.md)


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Canonical: https://rewindex.com/company/klaviyo/incidents/1ht269mmldck · Markdown: https://rewindex.com/company/klaviyo/incidents/1ht269mmldck.md · JSON: https://rewindex.com/api/v1/companies/klaviyo/incidents/1ht269mmldck · Generated 2026-10-18T11:29:08.358Z