Confidentiality, integrity and availability are essential features for devices connected to the Industrial Internet ofThings. However, cybersecurity was never a main concern for power electronics because most of the devices were designed to operate in an isolation mode, without connectivity and data transfer with other devices. With the digital transformation and the industry 4.0, there was a disruptive change in this scenario. Companies, governments and universities have been studying and developing mechanisms to mitigate vulnerabilities in these devices. This article is a literary review on cybersecurity in power electronics with an introduction on digital transformation, industry 4.0 concepts and cybersecurity in the Industrial Internet of Things, presenting some real cyberincidents, tools adopted by companies and researches.