LoFP LoFP / b2b collaboration migrations where external users are intentionally promoted to full membership. organizational restructuring that converts former contractors to permanent employees in place.

Techniques

Sample rules

Entra ID Guest Account Promoted to Member

Description

Identifies Entra ID user accounts converted from Guest to Member type via an Update user operation. A Guest-to-Member conversion grants the account full directory read access, removes external-identity Conditional Access restrictions, and makes the account indistinguishable from an internal employee. An attacker who compromises a guest account and promotes it to Member type gains persistent tenant access without triggering role assignment alerts.

Detection logic

data_stream.dataset: "azure.auditlogs" and
azure.auditlogs.operation_name: "Update user" and
azure.auditlogs.properties.target_resources.*.modified_properties.*.display_name: "UserType" and
azure.auditlogs.properties.target_resources.*.modified_properties.*.old_value: *Guest* and
azure.auditlogs.properties.target_resources.*.modified_properties.*.new_value: *Member* and
event.outcome: (Success or success)