Intermittent errors with app installation token authentication

Update timeline

1. investigating May 23, 2026, 04:00 PM UTC

   We are investigating reports of impacted performance for some GitHub services.

2. investigating May 23, 2026, 04:01 PM UTC

   We are seeing an increased rate of authentication failures for app installation tokens, affecting approximately 1% of tokens. We are continuing to investigate.

3. investigating May 23, 2026, 04:35 PM UTC

   We are continuing to investigate an elevated error rate of authentication failures for app installation tokens. Next update in one hour.

4. investigating May 23, 2026, 05:41 PM UTC

   We are seeing signs of mitigation and are continuing to monitor for complete mitigation. Next update in one hour.

5. investigating May 23, 2026, 06:42 PM UTC

   We see significant signs of mitigation and are monitoring for full mitigation.

6. investigating May 23, 2026, 07:06 PM UTC

   We have identified and are applying additional mitigation and will continue to monitor for complete mitigation.

7. investigating May 23, 2026, 07:32 PM UTC

   This is fully mitigated, we will continue to monitor to ensure it does not reoccur.

8. resolved May 23, 2026, 07:32 PM UTC

   This incident has been resolved. Thank you for your patience and understanding as we addressed this issue. A detailed root cause analysis will be shared as soon as it is available.