How to Ensure OTA Update Security

An over-the-air (OTA) update for an Internet of Things (IoT) device is a convenient way to provide customers with the latest security patches and features. Since these updates arrive over cellular data or Wi-Fi networks, customers can get them with little or no effort. 

Many companies have used OTA updates to quickly address known vulnerabilities in IoT devices, significantly reducing ramifications for device owners. However, OTA updates only work when people involved manage them securely. 

Vulnerabilities in OTA updates create entry points for hackers, allowing them to steal sensitive data, tamper with devices, or cause other problems. Prioritizing security for all OTA updates ensures they occur without problems. Here are six ways to bolster OTA update protections to help ensure security and prevent hacking.

1. Follow Best Practices 

Developers and others involved in creating and delivering OTA updates should begin by considering all the vulnerabilities hackers may target. Bart Stevens, the senior director of product marketing for security at Rambus, recommends several strategies to make OTA updates more secure: 

• Encrypt software updates
• Digitally sign updates after encryption
• Perform hostname verification to ensure clients connect to verified servers
• Use Transport Layer Security public key authentication 
• Have signed certificates with the public keys of the entities requesting the update

People must put themselves in hackers’ shoes to understand how they approach upcoming OTA updates. Then, they should look for and improve weak points to keep devices as secure as possible. 

2. Use the Secure Boot Process

The secure boot process is a safeguard that ensures only trustworthy software loads when the IoT device starts up. It checks the digital signatures of various components before allowing them to run. 

This preventive measure stops the IoT device from running malicious software or legitimate versions hackers have infiltrated. Since the secure boot process only allows signed and verified code to run on the device, using it significantly reduces cyber threats. 

3. Prevent the OTA Update From Interfering With Critical Processes

People must design their OTA updates so as not to disrupt a device's operation at critical times. Many cars, connected medical devices, and essential pieces of industrial machinery have IoT components that receive OTA updates. Context awareness is a crucial part of safe user experiences. 

OTA updates must only occur during noncritical times to avoid interfering with users or introducing hazards. One possibility is to distribute them outside a company’s operating hours. 

Many people use specialized platforms to manage and secure large numbers of IoT devices at once. This strategy works well for ensuring devices aren’t overlooked for updates. However, individuals using these management platforms may also wish to change settings to better time OTA updates. 

4. Suggest Customers Back up Data Before Updates Occur

People should abide by established data governance policies whenever they handle sensitive information — on an IoT device or otherwise. These policies increase efficiency, consistency, and security by dictating which parties manage data and creating a clear framework to follow. Policies vary by organization and the type of information it handles; however, many policies include backup stipulations. 

Even if things go wrong, the organization will have copies of its data. The fact that the company performed a recent backup should reduce the attack’s ramifications if hackers compromise the IoT device during an update. 

5. Remind People of the Importance of Password Hygiene

Even if an OTA update happens securely, hackers could still find ways to interfere with the device — such as when users do not have good password hygiene. IoT device makers should provide password-related tips and consider building specifications to prevent people from using those that are easy to guess. 

For example, manufacturers may require people to create an initial password to meet a certain length and include a mix of letters, numbers, and symbols. The registration form for an IoT device should also remind users to select unique passwords rather than reusing them across sites. 

6. Establish a Formal Testing Framework

During OTA updates, people can also uphold security by creating a formal testing framework to scrutinize the approach and target its weaknesses — a valuable decision for OTA updates affecting critical IoT products, such as connected cars. 

In one example, researchers validated and found vulnerabilities in connected cars' standardized OTA update system. Their work also involved modeling five attacks mimicking outside attackers and targeting compromised systems. 

Regardless of the affected industry, people should strongly consider creating internal frameworks to test their processes and procedures. Understanding vulnerabilities before they become problematic in the real world is a practical way to make updates more secure. This also heightens people’s awareness and gives them time to fix issues.  

Prioritize Security at Every Opportunity

These are some of the most effective ways to keep OTA updates as secure as possible. People must also continually evaluate their processes and look for viable ways to improve them. Focusing on such optimization will highlight weak areas and the system’s strong suits so everyone knows products are safe from cyberattacks. This enables people to use their devices with confidence.