Coverage Without Complexity: The Case for Agentless Network Scanning

The Problem

Agent-based security tools offer deep visibility, but they come with a cost: every device in scope needs to have an agent installed, maintained, updated, and monitored. In large, heterogeneous environments — spanning Windows, Linux, macOS, legacy systems, network devices, and OT equipment — achieving and sustaining full agent coverage is a significant operational challenge. Devices get missed during initial deployment. Agents fall out of date. Some device types simply cannot run agents at all.

The result is coverage gaps that are often invisible to the security team. Devices without agents don’t appear in agent-based dashboards, creating the illusion of full coverage while leaving real blind spots. An agentless approach addresses exactly these gaps — reaching devices that agents can’t or don’t cover.

The Use Case

Agentless network scanning means assessing the vulnerability posture of devices across the network without requiring any software to be installed on the target systems — using network-level probes, protocol interactions, and optionally authenticated queries to gather vulnerability data from devices that can’t or shouldn’t host agents.

How It’s Generally Solved

Network-based vulnerability scanners have been the traditional approach to agentless assessment. They use a scanning engine deployed on the network to probe target systems remotely, collecting data about open ports, running services, and in authenticated modes, internal system state. The challenge is ensuring scanner placement provides adequate coverage across network segments, VLANs, and remote locations — and that scan schedules are frequent enough to catch new vulnerabilities promptly.

In many environments, scan coverage varies across network segments, which leads to inconsistent visibility and missed devices.

How Saner CVEM Solves It

Saner CVEM integrates agentless scanning with asset visibility and prioritization, so devices without agents are included in vulnerability assessment and remediation workflows.

1. Discover Devices Across the Network

Saner scans network segments to identify devices that are reachable but may not have agents installed.

This includes:

• Workstations and servers without agents

• Network devices and appliances

• Systems in isolated or restricted environments

All discovered devices are added to the asset inventory.

2. Collect Vulnerability Data Without Installing Agents

The network scanner gathers data using remote probing and supported protocols.

Where access is available, authenticated queries provide deeper inspection. Where not, the scanner still captures exposure through network-level signals.

3. Combine Agentless and Agent-Based Data

Findings from agentless scans are merged with data from agent-based assessments.

This creates:

• A unified view of all assets

• Consistent visibility across device types

• Coverage across managed and unmanaged systems

4. Identify and Prioritize Vulnerabilities Across All Devices

Vulnerabilities detected through agentless scanning are evaluated alongside asset context.

Teams can:

• Spot high-risk devices without agents

• Compare risk across all systems

• Focus on vulnerabilities affecting important assets

5. Maintain Coverage Across Changing Environments

As new devices connect to the network, they are discovered and assessed without requiring manual onboarding.

This keeps visibility consistent even in environments where agent deployment is limited.