Intermittent Service Interruption Affecting api.ctmail.com

Update timeline

1. resolved Nov 12, 2025, 04:00 PM UTC

   Incident Summary Between approximately 10:09 PM ET on November 11 and 11:00 AM ET on November 12 , some customers experienced intermittent unavailability or slower-than-normal performance when accessing api.ctmail.com (Cyren Licensing API). What Happened An unexpected surge of legitimate traffic to one of our other APIs temporarily placed additional load on shared backend systems. This caused intermittent performance issues for the Licensing API and related services. Customer Impact Some customers were briefly unable to reach api.ctmail.com . Others may have noticed slower responses or occasional connection failures. The impact was intermittent and fully resolved by 11:00 AM ET on November 12 . Resolution Once the underlying cause was identified, our engineering team made targeted adjustments to increase system capacity and improve how connections are handled under high load. These changes quickly stabilized performance, and normal operation was fully restored. Preventive Measures We’re implementing additional improvements to prevent a recurrence, including: Enhancing how traffic is balanced across backend systems Expanding capacity for handling high connection volumes Strengthening monitoring to detect early signs of resource saturation Adding safeguards to prevent one service’s traffic from affecting others Current Status All systems have been operating normally since November 12 at 11:00 AM ET , and no further issues have been observed.