Why hardware write-protected USB drives are critical for Industrial Control Systems.

Honeywell’s recent cybersecurity report noted that 37% of threats are designed to spread via removable media, nearly doubling from 19% in 2020. That spike highlights how USB flash drives remain a weak link in Industrial Control Systems (ICS) if not properly managed.

Honeywell’s solution, Honeywell Forge, is software that monitors connected devices and flags risks [Ref:1]. Monitoring is useful, but it doesn’t prevent malware from getting in. Prevention requires the right kind of media in the first place.

Air-gapped systems and the USB problem

ICS environments are typically air-gapped—they’ve never touched the internet. Updates happen through portable storage, usually a USB flash drive. If that drive is compromised, malware bypasses all other defenses and lands directly in the control system. The only effective safeguard is a drive that is physically incapable of being infected while in transit.

Software tricks—like setting a read-only attribute with DISKPART or flipping registry rights—don’t cut it. Those methods are easy to reverse and offer little real protection against a determined attacker.

A hardware-level solution

The Lock License flash drive by Nexcopy takes a different approach. Its write protection is enforced at the hardware controller level. Unlike software locks, hardware-level controls cannot be undone with a few registry edits. This makes the device far more resistant to tampering or malware injection.

The Lock License design also balances usability. A content creator can temporarily unlock the drive with a password to write new data. Once disconnected, the drive automatically returns to its secure state: read-only. That means you can safely prepare update media in a trusted environment, then deploy it to an ICS without fear of the drive being altered along the way.

Final thought

It’s hard not to ask: why weren’t USB drives built like this from the beginning? For ICS, where uptime and safety are everything, a hardware write-protected flash drive isn’t just a convenience—it’s a necessity.

Nexcopy’s Lock License flash drive adds password-based control to hardware write protection.

Nexcopy has redefined how secure USB media can function with the Lock License flash drive. By default, the drive is read-only—completely write protected. Using Nexcopy’s Lock License utility, the user can temporarily unlock the device with a password to enable write access. Once power is cut, the device automatically reverts to its safest state: read-only.

Greg Morris, CEO of Nexcopy Inc., explains: “What makes the Lock License unique is that whenever power is cut, the USB automatically returns to write-protected mode. This first-line defense makes it impossible for malicious software or a virus to infect the drive.”

The initial password is set on first use. From that point on, the user controls when the drive is writable. The design offers businesses a practical balance between usability and security.

Key Features

• Default state is read-only (hardware write protection)
• User-defined password removes write protection
• No password required for reading; functions like a WORM device
• GUI and command line utilities available for unlocking
• No back-door access—Nexcopy cannot unlock the device
• Available in USB 2.0 and USB 3.0, from 2GB up to 128GB

Stan McCrosky, head of Sales at Nexcopy, points to industries such as utilities, petroleum, and waterworks as clear beneficiaries. “Being able to update firmware on a hardware write-protected USB ensures maximum in-field security. The command line utility lets manufacturers automate updates without leaving the drive in a writable state.”

How It Works

• Insert the Lock License USB into a Windows computer
• Launch the GUI or command line utility
• Enter the assigned password to unlock write access
• Load or update content on the drive
• Eject the drive—once disconnected, it reverts to read-only
• Read access is universal; password is only required for unlocking write access

Nexcopy offers the Lock License media in multiple body styles and colors suitable for custom branding. Options include Oxford (swivel style), Newport, Lexington, Augusta, Huntington, and Geneva. Oxford is the stocked model, available for same-day printing and shipping.

In stock, Nexcopy carries Oxford swivel drives in USB 2.0 (2GB, 4GB) and USB 3.0 (8GB through 128GB) capacities. Full-color branding is available through Nexcopy’s Logo-EZ printer.

The Lock License utility can be downloaded from Nexcopy’s support page. Note: the security function requires Nexcopy-licensed media—it cannot be applied to off-the-shelf USB sticks.