CVE-2026-31957 (GCVE-0-2026-31957)

Vulnerability from cvelistv5 – Published: 2026-03-11 19:25 – Updated: 2026-03-12 20:00
VLAI
Title
Himmelblau unset domain configuration can allow any-tenant authentication at first login for remote deployments
Summary
Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. From 3.0.0 to before 3.1.0, if Himmelblau is deployed without a configured tenant domain in himmelblau.conf, authentication is not tenant-scoped. In this mode, Himmelblau can accept authentication attempts for arbitrary Entra ID domains by dynamically registering providers at runtime. This behavior is intended for initial/local bootstrap scenarios, but it can create risk in remote authentication environments. This vulnerability is fixed in 3.1.0.
Severity
10 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-12 20:00 UTC
CWE
  • CWE-1188 - Insecure Default Initialization of Resource
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
himmelblau-idm himmelblau Affected: >= 3.0.0, < 3.1.0
guessed Create a notification for this product.
Show details on NVD website
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