# GitHub: Major incident: Disruption with Copilot Code Review

**Summary:** GitHub’s major Copilot code review incident ran from 2026-09-04 20:39 UTC to 2026-09-04 22:26 UTC (1 h 47 min). Affected pull request reviews failed to complete or post comments because an authentication-permissions change blocked submissions to the GitHub API; reverting the change restored normal operation. _(machine-written, sol)_
- Kind: Major incident · Label: outage (model (Jev))
- Changed: 2026-09-04 20:39 UTC · Detected: 2026-10-17 18:22 UTC
- [Source: https://stspg.io/dddfhld6fj0z](https://stspg.io/dddfhld6fj0z)
- [Company: GitHub](https://rewindex.com/company/github.md)
- Versions: before (none: first archived) → after incident\_version:187/zw1hbx2yyhvr@6baa167aa3df
- Change 1 of 1 for this incident

## What changed

**1. Added: Title**

```diff
+ Disruption with Copilot Code Review
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2026-09-04 20:39 UTC
```

**5. Added: Resolved time**

```diff
+ 2026-09-04 22:26 UTC
```

**6. Added: Update** (investigating) · 2026-09-04 20:39 UTC

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

**7. Added: Update** (investigating) · 2026-09-04 20:57 UTC

```diff
+ Some users may be experiencing failures when using Copilot code review. We have identified the root cause and are working on a mitigation.
```

**8. Added: Update** (investigating) · 2026-09-04 21:54 UTC

```diff
+ We are applying the mitigation and expect recovery within approximately 30 minutes.
```

**9. Added: Update** (monitoring) · 2026-09-04 22:25 UTC

```diff
+ The degradation has been mitigated. We are monitoring to ensure stability.
```

**10. Added: Update** (resolved) · 2026-09-04 22:26 UTC

```diff
+ On September 4, 2026, between 20:04 and 22:26 UTC, GitHub Copilot code review experienced an increased failure rate. Affected pull request reviews failed to complete or post review comments.<br /><br />The incident was caused by a change to the service’s authentication permissions that prevented it from submitting affected reviews to the GitHub API. We reverted the change and restored normal operation by 22:26 UTC.<br /><br />We apologize for the disruption.
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-09-04 20:39 UTC | Major incident: Disruption with Copilot Code Review (this change) | outage |

All GitHub changes: [timeline](https://rewindex.com/company/github/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._


---
Canonical: https://rewindex.com/change/i8f57a23b917e47 · Markdown: https://rewindex.com/change/i8f57a23b917e47.md · JSON: https://rewindex.com/api/v1/changes/i8f57a23b917e47 · Generated 2026-10-18T00:39:24.420Z