In the sprawling, intricate world of enterprise technology, the greatest threats often come not from sophisticated software exploits but from the most innocuous of components. A humble USB cable, a ubiquitous and often-overlooked peripheral, has become the latest vector for a highly deceptive hardware attack, revealing deep-seated vulnerabilities in the global technology supply chain that corporations rely on daily.

Researchers at the cybersecurity firm Eclypsium have uncovered what they’ve dubbed the “X-Ray” cable—a counterfeit version of the popular Keyspan USA-19HS USB-to-serial adapter. This isn’t a simple knock-off; it’s a meticulously engineered piece of hardware designed to trick not only the user but the very operating systems it connects to. The Keyspan adapter is a workhorse in industrial, medical, and data center environments, used to connect computers to networking equipment, industrial machinery, and other critical systems. The discovery, detailed in a report from Eclypsium, began when one of the firm’s own researchers found their newly purchased adapter was behaving erratically, prompting a deep-dive investigation that peeled back layers of sophisticated hardware deception.

The incident serves as a stark warning for Chief Information Security Officers and supply chain managers: the integrity of hardware can no longer be assumed. While the X-Ray cable itself was not found to contain a malicious payload, its ability to masquerade as a legitimate device and bypass multiple layers of security checks demonstrates a blueprint for more sinister attacks. If counterfeiters can manipulate firmware to ensure a device functions, they can just as easily embed code to steal data, install malware, or create a persistent backdoor into a corporate network.

A Counterfeit of a Counterfeit Detector

At the heart of the deception lies a tiny silicon chip, a Prolific PL2303-series USB-to-serial controller. Prolific Technology, the Taiwanese manufacturer of the chip, has been battling counterfeiters for years. In response, the company integrated anti-counterfeiting technology directly into its official device drivers, which are distributed through operating systems like Windows. When a genuine Prolific driver detects a counterfeit chip, it typically refuses to work, often displaying an error message to the user. This cat-and-mouse game has, for years, been a standard defense against a flood of low-quality clones.

The creators of the X-Ray cable, however, have taken this game to a new level. Instead of using a simple clone, they employed a counterfeit chip whose firmware was specifically altered to defeat Prolific’s security measures. According to security news outlet BleepingComputer, the chip is a counterfeit of a newer Prolific model that is designed to detect and block fakes. The counterfeiters effectively reverse-engineered the detection mechanism and programmed their chip to lie about its identity, successfully fooling the legitimate driver into accepting it as genuine.

This represents a significant escalation in hardware counterfeiting. It moves beyond simple imitation to active, intelligent evasion of security controls embedded in software. The cable is, in essence, a hardware Trojan, designed from the silicon up to deceive. The level of effort suggests a well-resourced and technically proficient operation, one that understands the interplay between hardware, firmware, and the software drivers that control them.

A ‘Frankenstein’ Device Bypassing Digital Gatekeepers

The Eclypsium team’s physical analysis revealed what they described as a “Frankenstein” device, cobbled together with a mix of components. The requires an X-ray to differentiate the counterfeit from the genuine article visually, hence the cable’s name. This physical complexity was mirrored in its digital signature. The modified firmware contained a crucial, and perhaps intentional, bug: it caused the chip to misidentify itself as a different model within the same Prolific family, a PL2303 GC-series, instead of its actual TA-series architecture.

This subtle misidentification is the key to its success. Modern operating systems, including Windows, macOS, and Linux, rely on a strict driver verification process. They check a device’s hardware IDs (Vendor ID and Product ID) to match it with a signed, trusted driver. As technology publication The Register notes in its coverage, the counterfeit cable presents the legitimate Prolific hardware IDs, allowing it to be paired with the official, signed driver. Because the driver is trusted by the operating system, the cable’s fraudulent nature goes completely undetected at the system level.

The firmware’s misidentification bug then bypasses the driver’s own internal anti-counterfeiting checks, which are designed for a different chip model. The result is a seamless user experience—the cable simply works, giving no indication of its duplicitous origins. It successfully navigates the security checkpoints of both the operating system and the manufacturer’s own driver, a feat that highlights a critical blind spot in a security model that implicitly trusts hardware to be what it says it is.

The Specter of Malicious USB Payloads

While this particular cable’s goal appears to be evading licensing and selling a functional counterfeit, the underlying technique opens the door to far more dangerous possibilities. The ability to modify firmware to bypass security checks is adjacent to the ability to modify it to execute malicious commands. This puts the X-Ray cable in the same threat category as infamous devices like the “BadUSB,” which demonstrated that the firmware of simple USB devices could be reprogrammed to act as malicious keyboards, network adapters, or data exfiltration tools.

The concept, first presented at a Black Hat security conference, showed that the trust we place in USB devices is fundamentally broken. An article in WIRED covering the initial BadUSB research explained how a device could tell a computer it’s a keyboard and silently type commands to download malware or steal files. The X-Ray cable proves that these capabilities are not just theoretical but are actively being refined in the wild by counterfeiters, who could easily be incentivized to add such payloads for state-sponsored actors or criminal syndicates.

For an enterprise, the implications are profound. An employee could purchase a replacement cable from an online marketplace, inadvertently introducing a hardware-based attack tool into a secure network. Traditional endpoint security software, which focuses on scanning files and monitoring software behavior, is often blind to threats operating at the firmware level. The device would be accepted by the system, and its malicious traffic or keystroke injections could be mistaken for legitimate user activity.

Addressing the Widening Cracks in Hardware Trust

This incident is a microcosm of a much larger crisis in supply chain integrity. The globalized nature of electronics manufacturing creates a complex and often opaque path from silicon fabrication to the end user, with numerous opportunities for counterfeit or compromised components to be introduced. Organizations face an enormous challenge in verifying the authenticity of the thousands of components that make up their IT infrastructure, from motherboards and network cards down to the simplest cables and adapters.

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has increasingly focused on these risks, recognizing that software defenses are insufficient if the underlying hardware is compromised. According to CISA, securing the supply chain involves managing risks associated with third-party vendors, suppliers, and service providers. The X-Ray cable demonstrates that this risk extends to even the most commoditized parts, which are rarely scrutinized with the same rigor as high-value assets like servers or CPUs.

Ultimately, the discovery of the X-Ray cable is a call to action for the technology industry. It underscores the need for a “zero trust” approach to hardware, where no component is trusted by default. This requires new methods of verification, such as cryptographic device attestation, more rigorous procurement policies that favor authorized distributors, and security solutions that can monitor and analyze hardware behavior at the firmware level. For now, the Trojan in the wire serves as a potent reminder that in the modern digital environment, the most dangerous threats can be hiding in plain sight, connected by a simple USB cord.