# CVE-2026-9132: Missing authorization vulnerability in GitHub Enterprise Server allowed disclosure of private repository contents via the Copilot pull request diff summary endpoint

> CVE-2026-9132: Missing authorization vulnerability in GitHub Enterprise Server allowed disclosure of private repository contents via the Copilot pull request diff summary endpoint. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-9132
Last updated: 2026-10-25T21:10:00Z

- Published: 2026-06-30 20:23 UTC · Updated: 2026-10-25 21:10 UTC · Assigner: GitHub\_P
- CVSS: 6.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS: 0.41%, 36th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-862

## Description

A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to read source code from private repositories they did not have access to. The    Copilot pull request description diff summary endpoint accepted a cross-repository comparison range and rendered the resulting diff without verifying that the requesting user was authorized to view    the target repository. Exploitation required an authenticated account on the instance with read access to at least one repository to use as the comparison base. This vulnerability affected all    versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.17.17, 3.18.11, 3.19.8, and 3.20.4. This vulnerability was reported via the GitHub Bug Bounty program.

## Affected vendors and products

- GitHub: Enterprise Server

## Tracked companies

- [GitHub](https://rewindex.com/company/github.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-9132)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-9132)
- [https://docs.github.com/en/enterprise-server@3.17/admin/release-notes\#3.17.17-features](https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.17-features)
- [https://docs.github.com/en/enterprise-server@3.18/admin/release-notes\#3.18.11-features](https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.11-features)
- [https://docs.github.com/en/enterprise-server@3.19/admin/release-notes\#3.19.8-features](https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.8-features)
- [https://docs.github.com/en/enterprise-server@3.20/admin/release-notes\#3.20.4-features](https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.4-features)

---

_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


---
Canonical: https://rewindex.com/cve/CVE-2026-9132 · Markdown: https://rewindex.com/cve/CVE-2026-9132.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-9132 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:14:28.824Z