CVE-2026-1999

A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to access internal services bound to loopback or unspecified addresses, potentially disrupting background job processing, accessing administrative endpoints, metrics, and profiling data, or manipulating job queues. Exploitation required an authenticated user with permissions to configure webhooks (repository, organization, or GitHub App administrator privileges). This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.14.22, 3.15.17, 3.16.13, 3.17.10, 3.18.4, and 3.19.1. This vulnerability was reported via the GitHub Bug Bounty program.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.22
https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.17
https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.13
https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.10
https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.4
https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.1

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::::::::

History

No history.

Information

Published : 2026-02-18 21:16

Updated : 2026-03-03 16:16

NVD link : CVE-2026-1999

Mitre link : CVE-2026-1999

CVE.ORG link : CVE-2026-1999

JSON object : View

Products Affected

github

enterprise_server

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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La explotaci\u00f3n solo fue posible en escenarios espec\u00edficos. Requer\u00eda un estado de solicitud de extracci\u00f3n limpio y solo se aplicaba a ramas sin reglas de protecci\u00f3n de rama habilitadas. Esta vulnerabilidad afect\u00f3 a las versiones de GitHub Enterprise Server anteriores a 3.19.2, 3.18.5 y 3.17.11, y fue corregida en las versiones 3.19.2, 3.18.5 y 3.17.11. 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