Kustomer has resolved an event affecting links and content utilising the default kustomer.help domain (not custom client domains) that caused visibility issues. After careful monitoring, our team has determined that all affected areas are now fully restored. Please reach out to Kustomer Support at support@kustomer.com if you have additional questions or concerns.

We are continuing to investigate this issue.

Kustomer is aware of an event affecting links and content utilising the default kustomer.help domain (not custom client domains) — including Help Center URLs and CSAT surveys — that may cause visibility issues. Our team is currently working to identify the cause of this issue in an effort to implement a resolution. Please expect additional updates within the next 30 minutes, please reach out to Kustomer Support at support@kustomer.com for any further questions or updates.

# **Summary** On September 7–8, 2026, some customers were unable to access Knowledge Base pages and related survey links hosted on the default `*.kustomer.help` domain. Customers using the default Knowledge Base domain in the prod1 environment encountered browser certificate warnings that prevented access to Knowledge Base content. Related links using the same domain, including some survey links, were also affected. Customers using custom Knowledge Base domains and shared Knowledge Base domains in other production environments were not affected. # **Root Cause** A security certificate used by the shared Knowledge Base domain expired before its renewal validation was completed. This caused browsers to reject connections to links served through that domain, while the underlying Knowledge Base service remained available. # **Timeline** **Sep 7, 2026** **8:00 PM ET**: Kustomer’s default Knowledge Base Domain certificate expired. At this time, customers may have begun encountering certificate warnings when accessing Knowledge Base content. ‌ **Sep 8, 2026** **8:37 AM ET** Kustomer receives reports of certificate warnings for default Knowledge Base Domain content and related links **8:38 AM ET** Kustomer Engineering is notified and begins our On-Call Incident Management process **9:00 AM ET** Kustomer Engineering identifies the shared-domain certificate issue and begins remediation steps **9:24 AM ET** Kustomer Engineering completes remediation steps **9:37 AM ET** Kustomer’s certificate provider acknowledges the remediation steps were complete and provisions a new certificate for the default Knowledge Base domain, restoring service # **Lessons/Improvements** Kustomer Engineering has a dedicated Infrastructure team that continuously works to maintain and improve Kustomer’s availability, reliability, fault tolerance. As part of our continual investment in these areas, we have identified the following action items related to this issue: * Move the shared-domain certificate to an automated renewal approach. * Add proactive monitoring and alerting for certificate expiration across shared customer-facing domains. * Review other certificates using the same renewal approach and prioritize any needed updates. * Document recovery procedures and ownership for certificate renewal activities.