CVE-2026-1355

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration identifier, an attacker could overwrite or replace a victim’s migration archive, potentially causing victims to download attacker-controlled repository data during migration restores or automated imports. An attacker would require authentication to the victim's GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. 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#3.14.23	Product Release Notes
https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.18	Product Release Notes
https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.14	Product Release Notes
https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.11	Product Release Notes
https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.5	Product Release Notes
https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.2	Product Release Notes

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

History

No history.

Information

Published : 2026-02-18 21:16

Updated : 2026-02-19 22:08

NVD link : CVE-2026-1355

Mitre link : CVE-2026-1355

CVE.ORG link : CVE-2026-1355

JSON object : View

Products Affected

github

enterprise_server

CWE

CWE-862

Missing Authorization

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By supplying the migration identifier, an attacker could overwrite or replace a victim\u2019s migration archive, potentially causing victims to download attacker-controlled repository data during migration restores or automated imports. An attacker would require authentication to the victim's GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. This vulnerability was reported via the GitHub Bug Bounty program."}, {"lang": "es", "value": "Se encontr\u00f3 una vulnerabilidad de falta de autorizaci\u00f3n en GitHub Enterprise Server que permit\u00eda a un atacante cargar contenido no autorizado a la exportaci\u00f3n de migraci\u00f3n de repositorio de otro usuario debido a una falta de verificaci\u00f3n de autorizaci\u00f3n en el endpoint de carga de migraci\u00f3n de repositorio. Al proporcionar el identificador de migraci\u00f3n, un atacante podr\u00eda sobrescribir o reemplazar el archivo de migraci\u00f3n de una v\u00edctima, lo que podr\u00eda hacer que las v\u00edctimas descargaran datos de repositorio controlados por el atacante durante las restauraciones de migraci\u00f3n o importaciones automatizadas. Un atacante requerir\u00eda autenticaci\u00f3n a la instancia de GitHub Enterprise Server de la v\u00edctima. Esta vulnerabilidad afect\u00f3 a todas las versiones de GitHub Enterprise Server anteriores a la 3.20 y fue corregida en las versiones 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. 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