CVE-2026-31957: critical vulnerability in himmelblau-idm himmelblau
Himmelblau unset domain configuration can allow any-tenant authentication at first login for remote deployments
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 10epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Affected products
himmelblau-idm · himmelblauRelated CVEs — himmelblau-idm himmelblau
In the same product, most dangerous first.
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