CVE-2026-45108

Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. From 2.0.0 to before 3.1.5 and 2.3.11, Himmelblau contained an authentication bypass vulnerability in the Device Authorization Grant (DAG) flow that allowed a user within the same Entra ID domain to obtain a local Unix session as another user by providing their own valid credentials. The vulnerability existed in the token_validate function, which validated domain aliases for legitimate multi-domain scenarios but failed to verify that the local part (username) of the authenticated user's UPN matched the requested account username. The function only compared domains, not the complete usernames. This vulnerability is fixed in 3.1.5 and 2.3.11.

CVSS v3 8.4 HIGH

8.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/himmelblau-idm/himmelblau/security/advisories/GHSA-pmxh-j4r6-88mv

Configurations

No configuration.

History

26 Oct 2026, 11:10

Type	Values Removed	Values Added
Summary		(es) Himmelblau es una suite de interoperabilidad para Microsoft Azure Entra ID e Intune. Desde la versión 2.0.0 hasta antes de la 3.1.5 y la 2.3.11, Himmelblau contenía una vulnerabilidad de omisión de autenticación en el flujo de Device Authorization Grant (DAG) que permitía a un usuario dentro del mismo dominio de Entra ID obtener una sesión Unix local como otro usuario al proporcionar sus propias credenciales válidas. La vulnerabilidad existía en la función token_validate, que validaba alias de dominio para escenarios legítimos de múltiples dominios, pero no verificaba que la parte local (nombre de usuario) del UPN del usuario autenticado coincidiera con el nombre de usuario de la cuenta solicitada. La función solo comparaba dominios, no los nombres de usuario completos. Esta vulnerabilidad está corregida en las versiones 3.1.5 y 2.3.11.

Information

Published : 2026-05-27 20:16

Updated : 2026-10-26 11:10

NVD link : CVE-2026-45108

Mitre link : CVE-2026-45108

CVE.ORG link : CVE-2026-45108

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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