The Hidden Risks of Agentless Devices: How to Secure Your Expanding Attack Surface

If I’m a hacker, I’m not wasting time trying to breach a laptop with multi-factor authentication, endpoint detection, and regular patches. Why would I? There are far easier targets quietly sitting on your network: agentless assets. Whether it’s the workhorses of your operations like industrial systems in factories, medical devices in hospitals, or unassuming IoTs like security cameras and badge readers, these devices are my way in. 

The reality is, your attack surface isn’t just laptops and servers anymore. Unmanaged, agentless devices are quietly and rapidly proliferating, creating massive blind spots for traditional IT and security solutions. 

We recently published the Rise of the Machines Report 2024, which highlights just how pervasive this problem has become: 42% of all enterprise devices are agentless. These devices can’t support endpoint agents, lack basic protections, and are often unmanaged from IT’s perspective — frequently overlooked in security strategies. 

And here’s the deal: these devices aren’t just isolated risks. 13% of agentless devices connect to both the internet and internal systems, and each communicates with an average of 6.2 other devices. Internally, 69% of agentless devices talk to other systems, creating a “blast radius” that attackers can exploit. 

This blog dives into why agentless devices deserve your attention and how to start addressing these hidden vulnerabilities. If you’re ready to dive deeper, check out Rise of the Machines for actionable insights on tackling these risks. 

Beyond Laptops and Servers: Why Agentless Devices Are Your Network’s Biggest Blind Spot 

For years, security teams have focused on agent-based tools to protect traditional devices like laptops and servers. Here’s the truth: agentless devices are where the real risks are — and they’re growing fast. 

According to our report, 64% of all mid- to high-level enterprise risks come from agentless devices. It’s not surprising. These devices can’t install endpoint agents, often lack basic protections like encryption or authentication, and are easy targets for attackers. 

What makes agentless devices even harder to manage is their diversity. They’re not a single category — they span mission-critical systems and everyday IoT gadgets, each with its own challenges. 

Mission-Critical Devices: The Backbone of Operations 

These are the operational backbone of your organization: 

• PLCs (Programmable Logic Controllers) in factories that manage automation. 

• CT scanners and medical devices in hospitals that directly impact patient outcomes. 

• Building management systems like air conditioners, elevators, and fire alarm systems. 

When these devices go down, it’s not just a security issue — it’s a business issue. Production stops, regulations are violated, and lives can even be at risk. Many of these devices are legacy systems, meaning they run older operating systems, are not easy to patch, and require robust segmentation and monitoring to stay secure. 

IoT Devices: Everyday Gadgets, Extraordinary Risks

IoT devices may seem less critical, but their volume and connectivity make them equally concerning, such as: 

• Printers, phones, digital signage, and media devices. 

• Smart thermostats, lighting systems, and security cameras. 

• Rogue third-party routers, entertainment streaming devices, and Wi-Fi-to-LTE bridges. 

Once compromised, these devices act as gateways for lateral attacks, giving attackers easy access to more sensitive systems. With IoT adoption surging, the risk compounds as every new device added to your network becomes a new potential entry point. 

Agentless devices — whether mission-critical or IoT — aren’t just weak links; they’re entry points. Addressing their unique risks is essential to reducing your attack surface. 

Shadow IoT and Swiss Cheese Networks: Uncovering Hidden Risks 

Let’s be honest: your network isn’t an iron curtain. It’s Swiss cheese. Every unmanaged device is another hole, and attackers only need one to get through. 

What’s worse is how mission-critical devices coexist with IoT devices, which are often consumer-grade gadgets or even banned hardware with high-risk software from foreign manufacturers. 

Polluted Networks: The Danger of Consumer and Banned Devices 

Our analysis uncovered alarming trends: 

• Networks polluted with consumer devices like Tesla vehicles, Alexa speakers, and Peloton bikes. 

• 50+ banned or high-risk devices in the average enterprise network, blending unapproved, unsecured, and mission-critical systems. Examples include banned Huawei surveillance cameras quietly bridging internal systems to external networks. 

IoT devices often operate independently, connecting to websites, URLs, and IPs. So, your challenge becomes determining whether that communication is normal or suspicious. 

Segmentation Shortfalls: Why VLAN Cleanliness Matters

Segmentation is supposed to help isolate high-value assets, but it often falls short. For example, 85% of VLANs in healthcare mix sensitive medical devices like CT scanners with unapproved devices, creating hidden pathways for lateral attacks. 

To address these shadow risks, ask yourself: 

• Do I know if banned or high-risk devices are creating pathways between my internal systems and the outside world? 

• Am I monitoring unexpected communication from IoT devices to risky endpoints? 

• Are mission-critical devices properly segmented, or are they sharing VLANs with IoT gadgets? 

By auditing communication patterns and cleaning up segmentation, you can significantly reduce the pathways attackers have to exploit. 

Agentless Device Vulnerabilities: How to Prioritize and Mitigate 

Vulnerabilities can feel overwhelming. You’re bombarded by thousands of them daily, and it’s impossible to patch them all. Here’s the thing: vulnerabilities are one of the easiest ways for attackers to breach your network. Ignoring them isn’t an option — but chasing every CVE isn’t the solution either. 

Context Over CVE Scores: What Truly Poses a Threat 

You need to prioritize, focusing on devices with high connectivity or critical roles. 

Ordr’s data highlights this challenge: 

• 63% of enterprise devices have critical CVSS scores (9-10), but not all are high-priority risks. 

• When context is factored in, only 15% of devices pose medium-to-high risks. 

A Smarter Strategy: Focus on High-Impact Risks 

The report also shows that 64% of agentless devices carry medium-to-high risks. These devices lack the protections of agent-based systems and can have outsized impacts if compromised. 

This is why context matters. It’s not just about CVE scores—it’s about understanding a device’s role, connectivity, and business impact. It’s also about knowing if the CVE has been exploited in the wild. By applying risk context, you can identify and focus on the small percentage of assets that pose the greatest threat to your operations. 

How to Minimize Your Attack Surface? Start By Asking Simple Questions 

Where do you start? Here’s where I would start: 

• What devices are on my network, and what’s their purpose? Who owns them and who authorized them? 

• Are banned or risky devices connecting to critical systems? 

• Do I know what low-reputation websites my devices are talking to? 

Awareness is the first step to control. Agentless devices are everywhere, operating quietly without oversight. If you’re not monitoring their behavior, you’re leaving your network open to risk. 

Every step you take toward greater visibility helps reduce your attack surface. For deeper insights, check out Ordr’s Rise of the Machines Report 2024. It’s packed with actionable strategies for managing and securing agentless assets. And if you’re looking for more, join me on December 12, 2024, at 10am PT/1pm ET for a live session on LinkedIn with Hacker Valley Media, where we’ll dive even further into these critical insights.