Mailgun outage: TLS Certificate Validation Errors for Clients Without SNI

Affected components

• API

1. resolvedApr 15, 2026, 15:34 UTC

   This incident has been resolved.

2. monitoringApr 15, 2026, 14:02 UTC

   A fix has been implemented and we are monitoring the results.

3. identifiedApr 15, 2026, 13:42 UTC

   The issue has been identified and a fix is being implemented.

4. investigatingApr 15, 2026, 13:40 UTC

   We are currently investigating an issue where customers making HTTPS requests to our API without Server Name Indication (SNI) enabled are being presented with an expired SSL/TLS certificate. This results in certificate validation failures for affected clients.

What APIStatus.watch saw

Our 5-minute checks didn't record a change in Mailgun's overall status around this incident. Smaller or regional incidents often leave a provider's overall status green.

Other services with incidents at the same time

Overlapping incidents aren't necessarily related.

• Confluent Cloud: Elevated error rates in AWS me-south-1 and me-central-1 regionsMajor · Apr 1, 2026, 19:52 UTC
• 1Password: SSO sign-in failing on some attempts for some usersMajor · Apr 13, 2026, 17:24 UTC
• GitBook: Git Sync executions are delayed due to third-party outageMajor · Apr 15, 2026, 15:34 UTC
• Inngest: Delays in function run schedulingMinor · Apr 15, 2026, 12:15 UTC

How often does Mailgun have incidents?

Mailgun reported 10 incidents in the last 90 days, 5 of them major or critical. A typical incident lasted 1h 17m. See Mailgun's uptime and incident history