CVE-2026-34397: medium-severity vulnerability in himmelblau-idm himmelblau
himmelblau: NSS fake-primary group lookup reintroduces name collision risk
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.2%
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.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Affected products
himmelblau-idm · himmelblauRelated CVEs — himmelblau-idm himmelblau
In the same product, most dangerous first.
CVE-2026-31957CRITICALHimmelblau unset domain configuration can allow any-tenant authentication at first login for remote deploymentsEPSS 0.5%CVE-2025-49012MEDIUMHimmelblau's Name-Based Group Matching in `pam_allow_groups` Leads to Potential Security BypassEPSS 0.4%CVE-2026-45108HIGHHimmelblau: Authentication Bypass via Cross-User Local Session Impersonation in Device Authorization Grant (DAG) FlowEPSS 0.2%CVE-2025-54882HIGHHimmelblau's Kerberos credential cache collection is world readableEPSS 0.2%CVE-2025-53013MEDIUMHimmelblau offline auth permits authentication with invalid Hello PINEPSS 0.2%CVE-2026-31979HIGHhimmelblaud-tasks: local privilege escalation via /tmp symlink attack on Kerberos ccacheEPSS 0.2%