Defending Your IoT Ecosystem: A Guide to Microcontroller Security

Defending Your IoT Ecosystem: A Guide to Microcontroller Security


The context of IoT has made security much more critical over the years. The significant number of connected devices makes it an attractive target for attackers, and several remote attacks have shown the vulnerabilities of device communication channels. Furthermore, with IoT, security extends the requirements for confidentiality and authentication to communication channels, which often require encryption.

Security in microcontrollers encompasses several aspects, including protecting firmware intellectual property, protecting private data in the device, and guaranteeing service execution.

As microcontrollers tend to come in wide varieties, evaluating and understanding microcontroller security in order to choose one that is the most suitable for their projects before making a selection can make an enormous difference to the overall security of a given IoT device, saving costs.

This blog sheds light on some of the most widespread cyberattacks listed below and helps build a secure system by showing which countermeasures to apply to such attacks.

8 Types of IoT Cyberattacks

Firmware Hijacking

A firmware hijack refers to a malicious code hackers enter into your device by using a backdoor, namely a path in the code allowing individuals to bypass security in the processor’s software. This malicious code can either be an unauthorized update on your computer or phone that results in malware or another cybercriminal activity.

By exploiting such gaps in security, hackers can remotely inject malware into firmware updates that appear to be legitimate.

Firmware hijacking can only happen if you’re not keeping up with your IoT firmware updates. So in order to counteract this problem, ensure that the firmware updates are from the expected source to prevent an attacker from hijacking the device and downloading malicious software.


The origin of most large-scale cybercrime is the botnet. A botnet attack consists of a group of bots and devices linked together to perform the same task for distribution and scaling.

Botnet attacks can turn IoT devices into remotely controlled bots, using smart, connected devices to transfer sensitive data.


DDoS refers to when a device or a service, such as a website, is unavailable to the user due to an immense traffic flow by forcing all devices to request service simultaneously.

When this happens, catering to incoming requests becomes overwhelming for the servers, exhausting their resources and bandwidth, resulting in the website it hosts either shutting down or slowing down. This leaves legitimate service requests unattended, thereby seriously impacting business.

You can realize a DDos attack and start taking the necessary steps by running a traffic analysis to identify malicious traffic or outsource DDoS prevention to cloud-based service providers, to name only a few.

Man-In-The-Middle Attack

A Man-in-the-Middle Attack is a cyberattack that occurs when a hacker eavesdrops on a two-party communication happening between a client and a manufacturer. This way, hackers can steal and manipulate the information they hear. 

For instance, by secretly breaching communications between two separate parties, the attacker starts communicating with both of them, making the recipients think they are receiving a legitimate message. For example, an attacker may send one of the recipients an email from their bank requesting that they log in to perform a certain given task. This way, the attackers’ fake website can steal their credentials and inflict further damage.

To ensure communication lines are not cut off, make sure that the security of the website used is encrypted.

SQL Injection Attack

SQL Injection is an injection attack that executes malicious SQL statements into the IoT device by avoiding authentication and authorization of a web page or application. After bypassing the application’s security measures, the attackers can retrieve the content of the entire SQL database behind a web application and add malicious codes to any input validation flaws, making unwanted changes to the program.

Moreover, attackers can use SQL Injection to add, modify, and delete records within the database.

Password Attack

Password attacks are cyberattacks in which hackers crack passwords with various programs and password-cracking tools. The different types of password attacks include brute force attacks, dictionary attacks, and keylogger attacks.

Phishing Attack

Phishing attacks are social engineering attacks in which an attacker impersonates a trusted contact and sends fake emails. 

The recipient then opens one of the emails and clicks on the malicious link or attachment. This way, attackers gain access to sensitive, confidential information.

Furthermore, phishing attacks can install malware on a given device.


Mainly originating from phishing attacks, a ransomware attack is a malware that locks down access to files by encrypting the given personal information and documents. The attacker then demands a ‘ransom’ payment, usually done through crypto-currency, for the decryption key in order for the victim to re-access the files.

This attack disrupts business operations and can lead to a considerable loss of money.


Device Protections & Solutions

Whether you have just become familiar with IoT or you’ve already invested in IoT, it’s important to have solutions to potential threats and regularly perform a cyber security audit to determine whether you need to take additional steps in order to protect devices.

Firmware Verification

Firmware verification refers to the microcontroller’s ability to validate software before it is executed. Each firmware component validates the subsequent component as it is loaded to ensure that the system only runs authenticated firmware.


The most common element related to IoT and microcontroller security is encryption. It is the most critical element in ensuring your software is protected and invisible to unauthorized persons, ensuring that data is transported securely.

Hardware Root of Trust (RoT)

Based on the idea that an intelligent system has an immutable and repeatable sequence that must be executed during initialization, a hardware root of trust (RoT) is the first and foremost foundation for securing an embedded system.

A microcontroller has an RoT when it starts by running trusted firmware. Moreover, if suitable flash protections are in their right places, the internal flash within the microcontroller can mimic such behavior.

Storage Security

Storage security and data protection become harder to extract when a microcontroller runs from an external flash, encrypting it to increase the difficulty of removing confidential information or credentials. 

In order to accomplish this, the encryption key needs to be unique to each device in case the breakage of one device will not compromise all the other similar ones.

Resistance to Injection Attacks

When a given product requires a certain defense mechanism against physical attacks, ensure that the chosen microcontroller implements countermeasures from a vendor and has mitigations in software, such as the ROM code and the bootloader.

Memory Protection

The memory protection unit (MPU) is a microcontroller hardware feature that allows memory protection for specified memory areas.

An MPU is used to assign access permissions to memory regions, which varies for each chipset. These regions can have subregions and could be configured to be as little as a few bytes long. Each of these regions could be restricted to only allow privileged access, set as read-only, or marked as non-executable.



IoT and microcontroller security are at the forefront of electronic devices, including the sensitive, confidential information and data that come with them.

In order to protect devices from cyberattacks, microcontrollers are a must, as they provide multiple solutions to IoT problems. With many high-quality products to choose from, you can rest assured that choosing the suitable microcontroller for your device and other application needs is now easier than ever.

If you want to find more Electronic Components Distributors, please check out the following articles:


Submit Requirement

Get Free Quote

 Request for Quote