The broker-to-local sync hook shouldSyncRemoteEndpoint only rejects a remote Endpoint if its subnets overlap the local cluster's own subnets. It does not verify that Spec.ClusterID matches the broker SA that created the CR, that Spec.Subnets are within the CIDRs declared in that cluster's Cluster CR, or that Spec.Subnets do not overlap other remote clusters' subnets. The accepted subnets are installed verbatim as WireGuard AllowedIPs and as Libreswan --client rightSubnet. A malicious spoke can publish an Endpoint with subnets covering arbitrary CIDRs (including 10.0.0.0/8 or 0.0.0.0/0), causing all matching traffic from peer clusters to be routed into the attacker's tunnel.

Source: Project Glasswing AI-SAST audit of submariner-io/submariner.
Finding ID: FIND-004
Assurance: execution_proven