Edge types

Source can directly invoke the target (completes an ExecutesAs escalation when code already attacker-controlled or config changed). Messaging sources include service-to-service invocations (API Gateway invoking Lambda, EventBridge invoking Lambda, etc.).

Source can reach target over the network (post SG/firewall/route evaluation). Messaging source/target covers publicly- or privately-reachable messaging endpoints (a queue/topic/event-bus with a public resource policy is an internet-reachable target; a private messaging endpoint is a private-link source/target) - consistent with ExposedToInternet and PrivateReachability, which already admit the Messaging class.

Source can cause the target to execute (event source, schedule). Includes triggering compute workloads and orchestration workflows. AnalyticsService sources cover analytics engines that invoke compute as part of query execution (e.g. an Athena federated query invoking its Lambda data-source connector).

Reachable only via private networking (PrivateLink/PE/PSC) - needs a foothold in-network. Includes private APIs and messaging endpoints accessible only via interface endpoints, and object storage reached via a private/gateway endpoint (Azure Blob/Files PE, GCS via PSC). Network sources cover the endpoint/distribution itself acting as the reachability actor (e.g. a CloudFront distribution's OAC/OAI reaching a private S3 origin, or a Private Endpoint node).