CVE-2026-45108 (GCVE-0-2026-45108)

Vulnerability from cvelistv5 – Published: 2026-05-27 18:53 – Updated: 2026-05-28 13:54
VLAI
Title
Himmelblau: Authentication Bypass via Cross-User Local Session Impersonation in Device Authorization Grant (DAG) Flow
Summary
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.
Severity
8.4 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-28 13:54 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7797 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
himmelblau-idm himmelblau Affected: >= 2.0.0, < 2.3.11
Affected: >= 3.0.0-alpha, < 3.1.5
guessed Create a notification for this product.
Show details on NVD website
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