services / Google Cloud / Compute Engine forwarding rules

Manage layer 4 port forwarding rules within a Google Cloud load balancer. Like `forwardingRules`, but for global load balancing.

Multiple organizational functions may often reside within Compute Engine. However, abuse of forwarding rules requires leveraging additional risks in VM / VPC configuration, such as sensitive data or access broadcast on open VPC ports.

compute.​globalForwardingRules.​pscUpdate

Can not be used to change targets. Can be used to access Google managed services when the rule already directs traffic to a target service and the attacker has access to a particular source VM.

Risks

1. Network destruction (HIGH)
2. Lateral movement (BOOST)

Scope: HIGH

This privilege may grant access to sensitive data from a single organizational function, or allow interruption of a service supporting a single organizational function.

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