CVE-2026-76851

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 v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.20	Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.14	Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.11	Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.7	Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.5	Release Notes Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:github:enterprise_server::::::::
	cpe:2.3:a:github:enterprise_server::::::::
	cpe:2.3:a:github:enterprise_server::::::::
	cpe:2.3:a:github:enterprise_server::::::::
	cpe:2.3:a:github:enterprise_server::::::::

History

No history.

Information

Published : 2026-09-01 22:17

Updated : 2026-09-08 13:05

NVD link : CVE-2026-76851

Mitre link : CVE-2026-76851

CVE.ORG link : CVE-2026-76851

JSON object : View

Products Affected

github

enterprise_server

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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