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.
The product initializes or sets a resource with a default that is intended to be changed by the administrator, but the default is not secure.
Developers often choose default values that leave the product as open and easy to use as possible out-of-the-box, under the assumption that the administrator can (or should) change the default value. However, this ease-of-use comes at a cost when the default is insecure and the administrator does not change it.