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CVE-2026-34397 (GCVE-0-2026-34397)

Vulnerability from cvelistv5 – Published: 2026-04-01 17:25 – Updated: 2026-04-04 03:05
VLAI
Title
himmelblau: NSS fake-primary group lookup reintroduces name collision risk
Summary
Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. From versions 2.0.0-alpha to before 2.3.9 and 3.0.0-alpha to before 3.1.1, there is a conditional local privilege escalation vulnerability in an edge-case naming collision. Only authenticated himmelblau users whose mapped CN/short name exactly matches a privileged local group name (e.g., "sudo", "wheel", "docker", "adm") can cause the NSS module to resolve that group name to their fake primary group. If the system uses NSS results for group-based authorization decisions (sudo, polkit, etc.), this can grant the attacker the privileges of that group. This issue has been patched in versions 2.3.9 and 3.1.1.
Severity
6.3 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-04 03:04 UTC
CWE
  • CWE-269 - Improper Privilege Management
Assigner
References
Impacted products
Vendor Product Version CPE status
himmelblau-idm himmelblau Affected: >= 2.0.0-alpha, < 2.3.9
Affected: >= 3.0.0-alpha, < 3.1.1
guessed Create a notification for this product.
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