# CVE-2026-14340: An incorrect authorization vulnerability in GitHub Enterprise Server allows issue creation in unrelated public repositories

> CVE-2026-14340: An incorrect authorization vulnerability in GitHub Enterprise Server allows issue creation in unrelated public repositories. CVSS 5.0 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-14340
Last updated: 2026-10-25T16:10:00Z

- Published: 2026-07-01 21:03 UTC · Updated: 2026-10-25 16:10 UTC · Assigner: GitHub\_P
- CVSS: 5.0 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N
- EPSS: 0.43%, 37th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-863

## Description

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed a user-to-server token scoped to a GitHub App installation to perform certain write operations on public repositories outside the token's intended scope. This was possible because the authorization check only verified that the installation had read permissions on the target repository rather than verifying that the token's installation was explicitly granted access to that repository. An attacker who obtained a victim's user-to-server token could create issues, issue comments, commit comments, and private vulnerability reports on any public repository, appearing as the victim user with no indication of the app involvement. This vulnerability was fixed by adding a repository scope check for user-to-server tokens issued by global apps. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.2, 3.20.4, 3.19.8, 3.18.11, 3.17.17, 3.16.20. 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-2026-14340)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-14340)
- [https://docs.github.com/en/enterprise-server@3.16/admin/release-notes\#3.16.20](https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.20)
- [https://docs.github.com/en/enterprise-server@3.17/admin/release-notes\#3.17.17](https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.17)
- [https://docs.github.com/en/enterprise-server@3.18/admin/release-notes\#3.18.11](https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.11)
- [https://docs.github.com/en/enterprise-server@3.19/admin/release-notes\#3.19.8](https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.8)
- [https://docs.github.com/en/enterprise-server@3.20/admin/release-notes\#3.20.4](https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.4)
- [https://docs.github.com/en/enterprise-server@3.21/admin/release-notes\#3.21.2](https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.2)

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_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/)_


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Canonical: https://rewindex.com/cve/CVE-2026-14340 · Markdown: https://rewindex.com/cve/CVE-2026-14340.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-14340 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:16:53.906Z