# TLS Certificate Validation Errors for Clients Without SNI

- Provider: [Mailgun](https://down.guide/providers/mailgun)
- Confidence: Confirmed
- Impact: Partial outage
- lasted 1h 54m
- started 2026-04-15 13:40 UTC
- API
- id: DWN-aea60e4f20
- Official page: https://stspg.io/xc1w9hchy2bd

## Updates from Mailgun
### 2026-04-15 13:40 UTC: investigating
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.

### 2026-04-15 13:42 UTC: identified
The issue has been identified and a fix is being implemented.

### 2026-04-15 14:02 UTC: monitoring
A fix has been implemented and we are monitoring the results.

### 2026-04-15 15:34 UTC: resolved
This incident has been resolved.

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