In the evolving world of cybersecurity, one principle now dominates every executive discussion: Zero Trust. The concept — “never trust, always verify” — has become the defining framework for protecting modern digital ecosystems. Yet even the most sophisticated Zero Trust strategies can collapse when one critical factor is overlooked: unmanaged devices.

Every network has them. Devices without agents, without visibility, without governance, and lacking centralized control. They are the forgotten endpoints — smart sensors, industrial controllers, cameras, gateways, medical equipment, or smart TVs — that operate outside the normal scope of IT management. And they represent the most significant blind spot in modern enterprise security.

In 2025, unmanaged devices are no longer edge cases; they are the edge itself. Understanding and securing them is now a board-level priority — and a cornerstone of true Zero Trust implementation.

The Scale of the Problem: Why Unmanaged Devices Matter

According to industry research, unmanaged and shadow devices account for over 30% of all enterprise network connections, with more than half containing at least one exploitable vulnerability. These devices are not malicious by design — they are simply invisible to conventional IT tools. Yet that invisibility makes them ideal entry points for attackers seeking persistence and lateral movement. This invisibility also introduces silent risks to the organization, as hidden vulnerabilities can be exploited without obvious warning signs.

Every unmonitored camera, sensor, or gateway can become a backdoor. When aggregated across thousands of sites, the potential exposure is staggering — particularly in sectors such as healthcare, energy, automotive, and manufacturing, where uptime and safety are mission-critical.

The problem is compounded by the fact that unmanaged devices often cannot host traditional agents or endpoint protection tools. As a result, these devices frequently miss critical security updates and continue to run outdated software, making them easy targets for attackers. Their lightweight firmware, proprietary protocols, or remote locations make standard security models ineffective.

How Unmanaged Devices Undermine Zero Trust

Zero Trust assumes no implicit trust between users, devices, or applications. Access must be continuously verified based on identity, context, and risk, with multi factor authentication and robust access control playing a critical role in Zero Trust frameworks.

Here’s how unmanaged devices erode Zero Trust from within:

1. Identity Gaps – Without unique machine identities or valid certificates, devices cannot authenticate securely to networks or cloud services.
2. Policy Blindness – Security policies, including the company’s policies, cannot be enforced on endpoints that the system doesn’t recognise.
3. Lateral Exposure – Once compromised, unmanaged devices provide attackers with pivot points into managed environments.
4. Compliance Failures – Frameworks like NIST and the Cyber Resilience Act require full asset visibility and control to meet compliance standards; missing devices equal non-compliance.
5. Trust Decay – Each unidentified device weakens the overall trust graph, undermining the Zero Trust model itself.

In short, without device visibility and machine identity automation, Zero Trust is only half implemented.

The Rising Threat Landscape

Recent botnet campaigns — including Eleven11Bot and Mozi — highlight the growing exploitation of unmanaged IoT endpoints. Attackers increasingly target devices that lack patching mechanisms, security agents, or strong authentication. These devices are especially vulnerable to malware and malware infections, which can be exploited for malicious activity by malicious actors seeking to compromise networks, steal data, or disrupt operations. Once compromised, these endpoints become part of coordinated attacks that can disrupt critical infrastructure or exfiltrate sensitive data.

The convergence of IT and OT networks amplifies this threat, increasing the risk to the overall IT environment. Industrial systems once isolated from the internet are now connected for monitoring, analytics, and predictive maintenance. Unfortunately, every connection adds a new risk surface.

With machine-to-machine communication expected to dominate future network traffic, unmanaged devices have become the silent weak link in Zero Trust architectures.

From Blind Spots to Full Visibility: The Role of AI in Securing Unmanaged Devices

Manual discovery methods can’t keep up with the scale or dynamism of today’s connected ecosystems. That’s why AI-driven discovery has become essential.

KeyScaler 2025 introduces a next-generation Discovery Tool powered by artificial intelligence that autonomously scans networks to detect and profile every connected device — managed or unmanaged. This supports comprehensive device management by providing visibility into all devices across the network.

Key features include:

• Passive Network Analysis: Identifies devices by analysing traffic patterns, including fingerprinting mac addresses and operating systems signatures, without disrupting operations.
• Machine Learning Classification: Differentiates device types and functions to assess potential risk levels.
• Automated Onboarding: Registers previously unmanaged devices into the enterprise trust framework.
• Continuous Monitoring: Tracks device behaviour, status, and compliance posture in real time, incorporating endpoint detection for ongoing threat monitoring and response.

This approach replaces reactive discovery with continuous intelligence, ensuring that no device remains unseen.

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Machine Identity: The Foundation of Trust

Every Zero Trust strategy starts with identity — and for devices, that means machine identities. Managed devices are assigned and maintained with strong machine identities by IT, while an unmanaged device often lacks proper identity management, increasing security risks and bypassing critical controls. Without verifiable credentials, a device cannot be trusted, and without trust, no secure communication can occur.

KeyScaler 2025 automates the machine identity lifecycle for every device, regardless of vendor or operating environment. Certificates are provisioned, rotated, and revoked automatically, ensuring that each endpoint can prove its authenticity at all times.

This process turns unmanaged devices into known, governed entities, closing the trust gap that undermines Zero Trust enforcement.

Automated machine identity management achieves three key outcomes:

1. Elimination of default credentials and hard-coded keys
2. Consistent certificate policies across IT, OT, and edge networks
3. Real-time revocation when anomalies or breaches occur

By automating these processes, the IT team and IT teams can more efficiently monitor, secure, and enforce policies for both managed devices and unmanaged devices, reducing manual workload and improving overall security posture.

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Zero Trust in Practice: Automating Verification

Once device identities are established, Zero Trust enforcement becomes an automated cycle of verification, enforcement, and adaptation.

Through AI-supported policy engines, KeyScaler 2025 continuously evaluates:

• The context of device connections (location, time, workload, and access to network resources)
• The risk posture (firmware version, vulnerability status, behavioural anomalies)
• The compliance alignment (NIST, CRA, EO 14028 requirements)

If a device fails validation — for instance, by deviating from normal communication patterns — KeyScaler can automatically quarantine or revoke its credentials, blocking access to network resources for non-compliant devices. This ensures that trust is not static but continuously reinforced in real time.

Explore Zero Trust for IoT and learn how securing unmanaged devices is possible with advanced security tools.

Network Security: Safeguarding the Perimeterless Enterprise

In today’s perimeterless enterprise, network security is more critical than ever—especially as unmanaged devices proliferate across every environment. Each device connected to the organization’s network, whether known or unknown, represents a potential vector for data leakage and security breaches. Security teams must take a proactive stance by deploying layered security controls such as next-generation firewalls, intrusion detection and prevention systems, and robust network segmentation. These measures help contain threats and limit the lateral movement of attackers who exploit unmanaged devices.

Implementing a secure browser environment and enforcing strict security policies further reduces the risk of unauthorized access to sensitive data. Regular audits of network configurations and device connections are essential to uncover hidden vulnerabilities and ensure that only authorized devices are granted access. By continuously monitoring the network and updating security controls, organizations can minimize costly downtime and maintain a strong security posture—even as the number of devices connected to their networks continues to grow.

User Education and Awareness: Empowering the Human Firewall

Technology alone cannot eliminate the risks posed by unmanaged devices—empowered users are a critical line of defense. Organizations must invest in ongoing user education and awareness programs to ensure that every employee understands the security risks and potential data breaches associated with unmanaged and personal devices. Training should cover security best practices for configuring and securing personal devices, recognizing the risks of unmanaged endpoints, and following company policies for device usage.

Users should also be taught how to identify and report suspicious activity, helping to create a culture of vigilance and shared responsibility. By equipping users with the knowledge to make secure choices and respond appropriately to potential threats, organizations can significantly reduce the risks of data loss and security incidents stemming from unmanaged devices. Ultimately, a well-informed user base is essential to complement technical controls and strengthen the overall security of the enterprise.

Incident Response: Preparing for the Inevitable

No security strategy is complete without a robust incident response plan—especially when unmanaged devices are involved. Organizations must be prepared to respond swiftly to incidents involving sensitive data and potential data leakage. A comprehensive incident response plan should outline clear procedures for containing and eradicating threats, as well as for notifying affected stakeholders in a timely manner.

Enforcing tight security policies and utilizing secure browsers can help prevent unauthorized access to sensitive data, but regular audits of device connections are equally important for early detection of vulnerabilities. By establishing clear protocols for device access and data handling, organizations can limit the impact of security breaches and ensure that sensitive information remains protected. Proactive incident response not only mitigates the damage from inevitable incidents but also reinforces trust in the organization’s ability to secure its network and data.

The Compliance Imperative

Modern compliance frameworks no longer focus solely on documentation. They require proof of continuous control and place a strong emphasis on regulatory compliance.

For example:

• NIST 1800-32 mandates automated identity management for IoT.
• The EU Cyber Resilience Act (CRA) holds manufacturers accountable for security throughout a product’s lifecycle.
• EO 14028 emphasises machine identity and SBOM visibility across supply chains.

For organisations with unmanaged devices, achieving this level of governance manually is impossible. KeyScaler 2025 simplifies compliance by integrating automated validation and reporting into the daily operation of device security — converting compliance from a periodic audit to a continuous process.

Quantifying the Risk of Unmanaged Devices

To communicate the urgency of addressing unmanaged devices, CISOs must translate security risks into financial terms. Device Authority’s ROI Calculator helps quantify both the cost of inaction and the value of automation.

For example:

• The average IoT breach costs enterprises over £3 million in downtime and remediation.
• Manual certificate management consumes hundreds of staff hours annually, often resulting in productivity disruptions.
• Compliance violations can lead to fines exceeding 2% of global revenue.

By modelling operational efficiency, risk reduction, and compliance savings, organisations can build a compelling business case for automating device visibility and trust.

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Integrating Unmanaged Devices into the Zero Trust Framework

To secure unmanaged devices effectively, organisations must embed them into the Zero Trust lifecycle. The recommended process is as follows:

1. Discover: Use AI-powered scanning to identify all connected devices, including those that connect or are connecting to the network.
2. Classify: Categorise devices by type, location, and function. Examples include personal device, personal phone, personal laptop, mobile devices, unmanaged laptops, as well as devices used by third party contractors and remote workers. Consider the unique challenges of byod environments.
3. Authenticate: Assign machine identities and issue trusted certificates.
4. Authorise: Apply context-based access policies.
5. Monitor: Continuously track behaviour and compliance, including monitoring for the use of unapproved tools and saas apps.
6. Remediate: Automate revocation or segmentation upon anomaly detection.

This approach ensures that unmanaged devices transition from “unknown” to “known and governed,” restoring full trust alignment across the enterprise. Protecting sensitive company data requires secure storage, as unmanaged devices are prime targets for attackers.

The Cost of Ignoring the Problem

Ignoring unmanaged devices doesn’t make them disappear — it simply transfers their risk into the organisation’s critical systems, exposing the organization’s network to potential threats. The consequences can be severe:

• Supply Chain Compromise: Attackers exploit insecure endpoints to infiltrate upstream partners.
• Operational Downtime: Compromised OT devices can halt production lines or safety systems.
• Data Integrity Loss: Tampered sensors corrupt analytics and decision-making.
• Reputational Damage: Breaches involving IoT devices often attract high-profile media coverage.

In short, unmanaged devices represent a systemic weakness. Addressing them is not optional; it’s fundamental to long-term resilience.

Future Outlook: Autonomous IoT Defence

As AI continues to advance, the next frontier of Zero Trust lies in autonomous IoT defence — systems that can detect, assess, and respond to threats across billions of devices without human intervention.

KeyScaler 2025 lays the groundwork for this future with its combination of AI-supported automation, machine learning analytics, and policy-driven orchestration. Integrated device management plays a critical role in autonomous IoT defense by enabling centralized control, device enrollment, and enforcement of security policies across company-owned, BYOD, and unmanaged devices. By converting raw telemetry into intelligent action, Device Authority ensures that enterprises stay ahead of both compliance demands and emerging threats.

Looking ahead, organisations that integrate AI-based trust frameworks today will be the ones best positioned to secure the hyper-connected landscapes of tomorrow.

Conclusion: Closing the Trust Gap

Unmanaged devices are the unseen threat that erodes Zero Trust from the inside. Every unknown connection represents a potential breach, a compliance failure, and a risk to operational continuity.

By leveraging AI-powered discovery, machine identity automation, and continuous policy enforcement, Device Authority enables enterprises to close this trust gap once and for all.

With KeyScaler 2025, every device becomes visible, authenticated, and governed — transforming Zero Trust from a theoretical ideal into an operational reality.

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