Network Device Detection

What are Rogue Devices on a Network?

Rogue devices are unauthorized, unmanaged, hidden, or spoofed hardware connected to a network without the organization’s knowledge or approval. These devices can create security blind spots, bypass existing controls, and introduce significant cyber risks.

Rogue devices may include unauthorized laptops, rogue access points, IP KVMs, mouse jigglers, USB-based implants, IoT devices, and hardware designed to impersonate legitimate assets. Because many of these devices operate below the visibility of traditional IT and security tools, they can remain undetected while providing attackers with access to sensitive systems, networks, and data.

Continuous hardware asset visibility is essential for identifying hidden devices, detecting hardware-based threats, and maintaining control over the attack surface.

Why Is Rogue Device Detection Critical

Every unidentified device represents a potential gap in an organization’s cybersecurity posture. Whether introduced intentionally or accidentally, unknown hardware can expand the attack surface, create compliance concerns, and complicate incident response efforts.

Traditional security tools are often designed to monitor users, software, and network traffic rather than validate the identity of connected hardware. As a result, unauthorized devices, spoofed equipment, and undocumented infrastructure can remain connected for extended periods without being detected.

Continuous rogue device detection helps organizations establish trust in their asset inventory, improve security operations, strengthen Zero Trust initiatives, and reduce the likelihood of hardware-based threats impacting business operations. By identifying connected assets as they appear, security teams gain the visibility needed to investigate anomalies, enforce policies, and respond more effectively to emerging risks.

Rogue Device Detection Case Study

A Tier 1 bank audit revealed some irregularities. It became evident that invisible network devices, rogue devices, had continuous access to the internal and secured parts of the network. After investigating the bank’s computing assets, including the servers, desktop workstations, and management’s laptop, the team found no evidence of malware with remote access capabilities.

Subsequently, investigations focused on deep monitoring of the in going and out going communications from the network hoping there would be an indication as to what was occurring. Again, the investigators found no evidence of full remote access. The bank sought assistance from the cybersecurity investigations practice of a leading global consulting firm. The team discovered that the perpetrators had cloned an authentic laptop, spoofed laptop, belonging to the bank. It was connecting to the network infrastructure via an out-of-band channel in parallel to the existing and legitimate laptop, similar to hidden remote access devices such as IP KVMs, which can bypass traditional security controls.

The network access profile, certificate, and other authentication measures were authentic and valid, meaning none of the existing security and monitoring tools could detect it as a rogue device on network. The attackers had employed a “ghost” malicious device that remained undetected. Upon further investigation, the team found an unidentified small hardware device installed in one of the distribution cabinets. This device provided the attackers with remote access, completely bypassing existing security measures.

Rogue Device Attack Study

With the growing sophistication of cyber threats, the concept of detecting rogue devices on network has become a crucial focus in ensuring network security. As new technologies emerge, attackers continue to innovate, using tools that are harder to identify.

The attackers used a legitimate off-the-shelf network router sold by a third party. Besides its other modus operandi, the device supports a virtual cable mode whereby two devices can be paired, and each installed at different locations while operating as if they are interconnected using a standard passive LAN cable. The two devices are able to reroute and tunnel the communication via a simple switchboard application. The device enables the interception of traffic and injection of data packets, streaming them back into the network. In addition to being able to carry out more complex man-in-the-middle (MiTM) attacks.

These rogue devices were particularly challenging to detect as they did not have an IP or MAC address. As a result, traditional Intrusion Detection Systems (IDS), Network Access Control (NACs), and network monitoring tools failed to identify them. The manipulation occurred on the Physical Layer and the Data-Link Layer (Layer 2), where higher-level communications appeared authentic and secure, complicating the detection process.

How Rogue Devices Bypass Authentication Methods

In this specific incident, the perpetrators utilized a BeagleBone board running USBProxy. When attached to the scanning device and the computer system that stores the records of genuine handprints, allowed the attacker to bypass the authentication.
The BeagleBone does not require any extra hardware in addition to its superior set of input/output features. Making it easy to interface with exterior electronics.

This highlights a key weakness in traditional security measures: rogue devices can easily bypass conventional authentication methods. The use of specialized hardware like the BeagleBone board underscores the importance of continuous monitoring and rogue device detection software that can identify these devices based on their physical attributes, rather than relying solely on their behavior.

Sepio’s Rogue Devices Detection and Mitigation

Sepio is the leader in rogue devices detection software. The company is disrupting the cybersecurity industry by offering solutions that can detect unauthorized or invisible network devices. Sepio’s technology prevents hardware-based attacks that operate over network and USB interfaces by identifying rogue devices on network in real time.

Sepio’s Asset DNA technology, rooted in the physical layer, relies on the existence of devices rather than their behavior. Enabling the discovery and identification of all managed, unmanaged, hidden or invisible network devices. Through innovative methods and machine learning algorithms, Sepio gets to the true source of asset risk, free from misleading profile perceptions and behavioral assumptions.

The rogue device detection software provided by Sepio platform strategically prioritizes assets based on their risk levels and implements precise hardware access controls. It automatically blocks devices that violate preset rules or are recognized as known attack tools.

Having comprehensive visibility of all network devices is crucial for effective hardware defense. However, the true value lies not just in identifying these devices, but in utilizing this information to proactively defend against them.

Sepio’s Asset Risk Management

Sepio’s technology provides real-time insights into network devices that require attention. By leveraging Asset DNA technology and policy rules, the system alerts users to high, medium, and low-risk devices, expediting resolution times, pinpointing regulatory gaps, and preventing hardware-based attacks. This actionable visibility empowers security teams to gain a deeper understanding of their device attack surface and manage hardware defense more effectively.

See every known and unknown devices. Prioritize and mitigate risks.
Schedule a demo. It will help you understand how to use Sepio’s patented technology to gain control of your asset risks.