CVE-2026-15783
mediumpriority · track · 0OT risk · elevatedEPSS 0.004 · 39 %ileDEEUEPSS · scored 2026-10-27
A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user with write access to any repository to read metadata from private repositories they did not have access to, including private repository owners and names, branch names, commit SHAs, commit messages, and the pushing actor. The delegated bypass endpoint resolved a rule suite directly from an attacker-supplied, encoded identifier without verifying that the requesting user could read the rule suite's repository, and because these identifiers are sequential an attacker could enumerate them across the instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.18, 3.18.12, 3.19.9, 3.20.5, and 3.21.3. This vulnerability was reported via the GitHub Bug Bounty program.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.3–5.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (15)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-2418Microsoft GitHub Enterprise Server: Mehrere SchwachstellenDeutsch2026-07-19csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Microsoft GitHub Enterprise Server ausnutzen, um einen Denial of Service Angriff durchzuführen, Daten zu manipulieren, Code auszuführen und Informationen offenzulegen.
also known as (3)
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sources
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references (15)
External citations — patches, advisories, analysis.
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.18cnnvd
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.12cnnvd
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.9cnnvd
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.5cnnvd
- https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.3cnnvd
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.18enisa_euvd
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.12enisa_euvd
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.9enisa_euvd
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