Increased errors with Core Transactional API

Mar 18th 2026 — Decryption Errors on API endpoints

Summary

Between 5:40 PM and 5:43 PM UTC on March 16, 2026, we experienced a brief issue during a key rotation that caused a small subset of API requests to fail due to decryption errors. These errors occurred within our system before any external processing took place.

The issue was quickly identified, and traffic was immediately redirected to a stable environment, restoring normal service.

What Happened

At 5:36 PM UTC, we routed traffic to a newly deployed cluster of our encryption service running with the latest security keys. Shortly after, we observed decryption errors affecting a small subset of records, which resulted in some requests returning 500 error responses. We promptly redirected traffic back to the existing cluster, restoring normal operation.

Further investigation determined that these records were still associated with a key in the process of rotation, and we updated them as a follow-up action to prevent the issue from recurring.

Next Steps

We have enhanced our process to ensure that a key’s usage is fully verified before it is removed from the encryption service.

-The Spreedly Team