CVE-2026-31957 — Himmelblau unset domain configuration can allow any-tenant authentication at first login for remote deployments
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 himm…
Published: 2026-03-11 · CVSS: 10.0 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7