Securing Third-Party IoT Devices in 2025: Best Practices for Protection
In 2025, with nearly 20 billion IoT devices worldwide, from smart thermostats to industrial sensors, these tools are revolutionizing how we live and work. However, third-party IoT devices often come with security risks due to inconsistent standards, weak protocols, and outdated firmware.
The 2016 Mirai Botnet, which disrupted major websites by exploiting unsecured IoT devices, serves as a stark reminder of these vulnerabilities. According to jumpcloud, “more than 50% of IoT devices have critical vulnerabilities that hackers can exploit right now.”
This article explores the risks of third-party IoT devices and outlines practical strategies to secure and monitor your IoT ecosystem effectively.
Why Third-Party IoT Devices Pose Risks
The rapid growth of IoT devices brings undeniable benefits, but their security challenges are significant. Weak default passwords, unencrypted data, and irregular updates make these devices prime targets for cyberattacks. Hackers can exploit them to steal data, disrupt operations, or even launch large-scale attacks. The good news? With the right approach, you can mitigate these risks and maintain a secure network. Below are ten best practices for securing and monitoring third-party IoT devices.
1. Know What’s on Your Network
You can’t secure what you don’t see. Untracked IoT devices are like hidden weak spots in your network, ready to be exploited.
- Inventory scanning: Use Nmap or Nessus to perform periodic network scans that detect and catalog every IoT device. Capture attributes such as manufacturer, model, MAC address, and firmware version.
- Cloud-based asset management: Leverage AWS IoT Device Management or Microsoft Azure IoT Hub to automate inventory updates and generate alerts for unknown devices.
Benefit: Ensures comprehensive visibility into all IoT endpoints.
2. Lock Them Down with Network Segmentation
A single compromised device, like a smart camera, shouldn’t bring down your entire network.
- Deploy IoT devices on isolated VLANs or subnets separate from sensitive systems (NIST SP 800‑190).
- Configure firewall rules to restrict traffic to essential services only.
- Apply zero‑trust principles: require mutual authentication and minimal permissions for device-to-device communication.
Benefit: Prevents lateral movement across your corporate network.
3. Strengthen Authentication
Weak credentials, like the default “admin” exploited in the Mirai botnet, are a major security gap.
Replace default credentials with strong, unique passwords. Use X.509 certificates for device-to-cloud authentication and enable multi-factor authentication (MFA) for admin access where possible. These steps lock out unauthorized users and keep your devices secure.
Benefit: Prevents unauthorized access and brute force attacks.
4. Stay on Top of Updates
Outdated firmware leaves devices vulnerable to known exploits.
- Subscribe to CVE Details feeds and vendor security advisories.
- Automate firmware patch deployment with tools such as AWS IoT Device Management or Balena.
- Retire end-of-life devices that no longer receive security updates.
Benefit: Closes security gaps before they can be exploited.
5. Monitor with Tools Like Nagios
IoT devices can show subtle signs of trouble, like unusual data spikes or rogue connections. Proactive monitoring catches these early.
Nagios XI and Nagios Network Analyzer let you set baselines for device behavior, track network traffic, and spot anomalies almost instantly. Nagios XI lets you monitor everything from CPU, Memory, and Disk usage and integrates it with Nagios Log Server for instant alerts.
Benefit: Enables early detection of potential threats, enhancing response times.
6. Encrypt Everything
Unencrypted data can be intercepted by attackers, allowing them to monitor user activity and steal sensitive information.
Ensure devices use TLS 1.3 for communication and MQTT with encryption for messaging. Use AES-256 for local data storage. Edge computing can also help by processing sensitive data locally, reducing exposure during transmission. These measures keep your data safe from eavesdroppers.
Benefit: Maintains confidentiality and integrity of IoT data.
7. Limit Who Can Touch Them
Physical access or unchecked admin privileges can lead to big problems.
Use tamper-evident seals to secure devices and role-based access control (RBAC) to restrict administrative access. Monitor logs for suspicious activity to catch unauthorized attempts early. Tight access controls protect your devices from tampering or misuse.
Benefit: Reduces risks from insider and outsider threats.
8. Test for Weak Spots
Waiting for hackers to find vulnerabilities is a risky bet.
Run regular penetration tests and vulnerability scans with tools like OpenVAS or Burp Suite. Simulate real-world attacks to identify weaknesses, such as unpatched firmware or weak encryption, before they’re exploited. This proactive approach keeps your defenses sharp.
Benefit: Ensures continuous improvement of security posture.
9. Check Your Vendors Carefully
Not all IoT manufacturers prioritize security, and a weak vendor can mean a weak device.
- Require vendor adherence to standards such as ISO 27001 or ETSI EN 303 645.
- Review vendor patch cadence, security disclosure policies, and transparency reports.
- Incorporate security requirements and liability clauses into procurement contracts.
Benefit: Reduces introduction of vulnerable devices.
10. Have a Plan for When Things Go Wrong
Breaches, like the 2021 Verkada hack where attackers accessed 150,000 cameras, highlight the need for preparedness.
Develop IoT-specific incident response plans with isolation protocols and detailed logging for forensic analysis. Regularly test these plans to ensure rapid response and containment during an attack.
Benefit: Minimizes impact and recovery time during real-world incidents.
Quick Look at IoT Security Practices
| Practice | Implementation | Benefit |
|---|---|---|
| Device Inventory | Scan and catalog with Nmap or Nessus | Ensures visibility of all devices |
| Network Segmentation | Use VLANs and zero-trust policies | Limits attack propagation |
| Authentication | Enforce strong credentials and MFA | Prevents unauthorized access |
| Firmware Updates | Automate patches and retire EOL devices | Closes known vulnerabilities |
| Monitoring (Nagios) | Analyze traffic and detect anomalies | Enables early threat detection |
| Encryption | Implement TLS 1.3, MQTT, and AES-256 | Protects data confidentiality |
| Access Control | Use RBAC and physical security measures | Reduces tampering risks |
| Vulnerability Assessments | Conduct scans and penetration tests | Identifies weaknesses proactively |
| Vendor Evaluation | Assess vendor security practices | Strengthens supply chain security |
| Incident Response | Develop and test response plans | Minimizes breach impact |
Final Thoughts
Third-party IoT devices are key to modern operations but carry real security risks. Keep a tight inventory, segment networks, enforce encryption, vet vendors, and monitor with tools like Nagios. Cyber threats are a matter of “when,” not “if.” These steps keep your IoT ecosystem secure and ready for action.
