CVE-2026-76851
highpriority · track · 35EPSS 0.008 · 57 %ileDEUSEPSS · scored 2026-10-27
A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance. Insufficient network isolation allowed malicious pre-receive hook code to impersonate an internal service and redirect trusted internal requests to a privileged service, leading to elevated code execution. Exploitation required pre-receive hook networking to be enabled and either site administrator privileges or write access to a repository containing a configured pre-receive hook. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.20, 3.18.14, 3.19.11, 3.20.7, and 3.21.5. 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 · medium–high · 5.2–8.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (27)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3151Microsoft GitHub Enterprise Server: Mehrere SchwachstellenDeutsch2026-09-01csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Microsoft GitHub Enterprise Server ausnutzen, um Informationen offenzulegen oder beliebigen Code auszuführen.
sources
Which sources assert this record, and when.
references (5) nvd
External citations — patches, advisories, analysis.
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.20
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.14
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.11
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.7
- https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.5
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