In manufacturing environments, cybersecurity is often built in layers: people, process, and technology. Within these layers of security, we find a range of technologies and practices- software solutions, firewall appliances, and various control processes that involve both people and technology. Those layers vary widely in cost and rollout time, but one high-impact place to a complete cybersecurity framework is industrial device hardening. Industrial device hardening is the process of securely configuring and reducing the attack surface of industrial control system (ICS) assets—such as PLCs, HMIs, drives, and industrial network devices—so they are more resistant to cyber threats, misuse, or unintended changes. Below are simple steps your team can take now to improve ICS security without overhauling your entire architecture.
1. Choose Certified Products
Why it matters: Starting with secure-by-design products reduces downstream hardening work.
Start with devices that are secure by design. Source devices from vendors who follow a formal secure development lifecycle, such as IEC 62443-4-1. This typically covers security requirements, secure design/implementation, verification and validation, defect and patch management, vulnerability handling, and end-of-life planning. When security is built into every stage it reduces the amount of hardening work you’ll need later.
2. Remove What You Don’t Need
Why it matters: Less surface, fewer surprises.
Every unnecessary service or feature is an open door for attackers. Disable nonessential services, close unused network ports, and turn off protocols you don’t require, such as Telnet. Removing default applications that aren’t needed in your production environment further minimizes your attack surface.
3. Configure Devices Securely
Why it matters: Intentional configuration reduces both human error and external risk.
All devices within your system must be configured securely to limit vulnerabilities. Take advantage of built-in security features and disable what you don’t need. Turn off unused communication protocols and interfaces like FTP, Wi-Fi, or Bluetooth, and enable protections such as signed firmware, secure boot, and access control. Document your approved configurations and keep them in a secure, version-controlled location for consistency.
4. Segment the Network
Why it matters: Segmentation contains issues and protects critical assets.
Segmentation is one of the most effective ways to contain risk. Follow the principles of defense-in-depth to group assets into zones based on their function and criticality. Separate critical assets from less critical or higher-risk components of the system.
5. Patch With a Plan
Why it matters: Timely updates close known holes without disrupting operations.
Regularly update your system with security patches and firmware updates. Timely updates close known vulnerabilities, but they need to be managed carefully. Test patches and firmware updates in a staging environment before deploying them to production. Prioritize updates based on the criticality of the vulnerability being addressed by the patch.
6. Lock Down Defaults
Why it matters: Predictable settings are easy targets.
Default settings are predictable and easy to exploit. a. Avoid using default configurations provided by the vendor. Change all default credentials immediately and disable any unused accounts. Update default user settings, and customize network switches, firewall, and security appliance configurations. Where accounts are required, enforce strong, unique passwords that meet your organization’s security policy.
7. Secure Backup and Restore
Why it matters: Fast, clean recovery limits downtime and impact.
A secure backup strategy is your safety net. Encrypt backups and store them in a secure or off-site location. Just as important, test your restoration process regularly to ensure it works as intended and doesn’t introduce new risks. A backup is only as good as your ability to restore it quickly and cleanly.
Where to Go from Here
Many of these hardening concepts can be implemented manually but automation tools can make the process faster and more consistent. If you’d like help, our team can support secure network design, device configuration baselines, and team training so you can move forward with confidence.
Charlie Dahlstrom | Industrial Network & Cybersecurity Specialist
Charlie Dahlstrom is an expert in secure network architecture for manufacturing and industrial environments. With a BA in Information Systems Management from Wayne State University and 12 years of experience in business development and industrial technology, he combines technical and business insight to drive networking and cybersecurity initiatives. Passionate about the rapid evolution of manufacturing technology, Charlie advises newcomers to “be a sponge—listen and learn from those with experience.”