CVE-2025-59044 Himmelblau vulnerable to GID collision via group name-derived mapping (privilege escalation)
Attackers can gain unauthorized access to resources by creating Entra ID groups with names matching privileged groups, causing GID collisions on Himmelblau-joined Linux hosts.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-59044?
CVE-2025-59044 is a medium-severity vulnerability in himmelblau-idm himmelblau, published on 9 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. Himmelblau 0.9.x derives numeric GIDs for Entra ID groups from the group display name when himmelblau.conf `id_attr_map = name` (the default configuration). Because Microsoft Entra ID allows multiple groups with the same `displayName` (including end-user–created personal/O365 groups, depending on tenant policy), distinct directory groups can collapse to the same numeric GID on Linux. This issue only applies to Himmelblau versions 0.9.0 through 0.9.22. Any resource or service on a Himmelblau-joined host that enforces authorization by numeric GID (files/dirs, etc.) can be unintentionally accessible to a user who creates or joins a different Entra/O365 group that happens to share the same `displayName` as a privileged security group. Users should upgrade to 0.9.23, or 1.0.0 or later, to receive a patch. Group to GID mapping now uses Entra ID object IDs (GUIDs) and does not collide on same-name groups. As a workaround, use tenant policy hardening to restrict arbitrary group creation until all hosts are patched.
Weakness: CWE-1188
Which versions are affected by CVE-2025-59044?
How do I fix CVE-2025-59044?
Upgrade to a fixed version.
Is CVE-2025-59044 being exploited?
There is no known exploitation of CVE-2025-59044 in the wild and no public exploit code.