Outbound network access is a system’s ability to start connections to external services, public APIs, or the internet. In cybersecurity, this is called egress. It matters because once a machine can talk out, it can send stolen data, fetch malware, contact a command-and-control server, or reach services that were never meant to be in scope.
Defenders usually treat outbound access as a high-risk capability and restrict it by default. Common controls include egress filtering, proxy allowlists, DNS restrictions, network segmentation, and logging of destination IPs and domains. In AI agent and evaluation environments, outbound access can be especially dangerous: a test system that should stay isolated may accidentally touch real services or public infrastructure. Strong controls help prevent accidental exposure, unauthorized data transfer, and remote manipulation.