2 Security

Enhancing the security of a system necessitates the implementation of several critical features:

• Confidentiality
• Integrity
• Authentication

The Confidentiality ensures that sensitive data remains inaccessible to unauthorized individuals or devices. The primary objective for firmware developers is to safeguard the applications from unauthorized access or duplication by competitors, thereby maintaining the confidentiality of the code. The aim is to restrict access to the intended devices, which are the sole authorized entities to utilize the code.

Microcontrollers are often equipped with security features that prevent malicious entities from accessing the program code stored within the device. Nevertheless, when firmware updates are required in the field, manufacturers must distribute the updated firmware to customers, enabling them to update the devices independently. This process could potentially allow to reverse engineer the firmware and access the original code.

The Authentication verifies the source of firmware, confirming its release by an authorized manufacturer rather than an unauthorized entity. The ability to update device firmware poses a risk of unauthorized software installation, potentially crafted by third parties with malicious intent to bypass security protocols or exploit device functionalities.

In addition, there is a risk that legitimate firmware could be misappropriated for use on unintended devices, such as unauthorized hardware clones or devices engineered for hacking. This represents a concern for authentication, this time with the target device.

The Integrity is essential for detecting any alterations to the data. For instance, an authorized firmware might be tampered with in a manner that it still appears authentic, yet it could facilitate attacks akin to those previously mentioned. Ensuring data integrity is, therefore, crucial for maintaining the overall security of the system.

Firmware without security measures is vulnerable to attacks that compromise confidentiality, integrity, and authenticity. Therefore, it is essential to implement strategies to strengthen these three critical areas. Several methods exist to ensure an unauthorized user has not intentionally altered firmware. These methods are outlined in the subsequent sections.