CVE-2026-31957 | Himmelblau is an interoperability suite for Microsoft Azure … | CVSS 10.0 CRITICAL

Description

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.

Metadata

CVE ID: CVE-2026-31957
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-03-10 15:40 UTC
Published: 2026-03-11 19:25 UTC
Last updated: 2026-03-12 20:00 UTC
Primary CWE: CWE-1188
CWE-1188: Insecure Default Initialization of Resource
Vendor / Product: himmelblau-idm / himmelblau
Sources: cve.org · NVD

Severity & Metrics

10.0 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

SSVC — CISA Coordinator

Exploitation: none
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
himmelblau-idm	himmelblau	—	>= 3.0.0, < 3.1.0

Weakness (CWE)

CWE	Source	Description
CWE-1188	cna	CWE-1188: Insecure Default Initialization of Resource

CVSS scores (1)

Score	Severity	Version	Source	Vector
10.0	CRITICAL	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

References (1)

https://github.com/himmelblau-idm/himmelblau/security/advisories/GHSA-q746-m2wv-qh4v https://github.com/himmelblau-idm/himmelblau/security/advisories/GHSA-q746-m2wv-qh4v