services / Azure / Virtual network subnet

A subnet is a segment of a virtual network's address space, used to isolate groups of resources and as the attachment point for NSGs, route tables, service endpoints, and delegated services.

Subnets are the unit of network segmentation within a VNet; control-plane privileges on it — altering address ranges, NSG/route-table associations, delegations, or attaching unauthorized resources into it — can enable significant privilege escalation via lateral network access (per the CRITICAL definition in services/README.md).

Microsoft.​Network/​virtualNetworks/​subnets/​joinLoadBalancer/​action

Required to attach a load balancer front end into the subnet. Lets an attacker insert an attacker-controlled load balancer into a specific subnet, enabling interception or redirection of traffic destined for resources on it.

Risks

1. Network movement (BOOST)

Scope: CRITICAL

This privilege may grant access to sensitive data from a significant fraction of organizational functions, allow interruption of critical organizational services, or its exploit could lead to significant privilege escalation.

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