The Internet of Things (IoT) technology brings numerous benefits and makes human life more convenient. Various modern systems are IoT-based, e.g., healthcare, monitoring, and transportation. However, the novel COVID-19 increases the need for IoT-based systems that intend to reduce human engagement to withstand the harmful consequences of physical distancing, also to increase systemsâ‚TM efficiency. The IoT sensors can sense and share data with other system entities. However, sharing relevant data over the public channel is subject to numerous security concerns. Fortunately, authentication is an important security service that can protect systems against potential attacks, e.g., reply, impersonation, DOS, man-in-the-middle, and lost/stolen smart card attacks. The authentication scheme should ensure mutual authentication among honest entities before gaining access and thus preventing unauthorized access. It is worth mentioning that the perfect authentication scheme should be secure against potential attacks. Additionally, due to the resource limitations, authentication scheme should be lightweight. In this context, many authentication schemes are proposed. Unfortunately, most of the existing authentication schemes are vulnerable to several attacks. Accordingly, IoT-based security is still an open research area that require further study. Hence, this abstract is about the analysis of the weaknesses associated with existing authentication schemes, which can help design new secure and lightweight authentication schemes. The COVID-19 pandemic has forced many changes onto the way we live and work. Physical distancing, travel restrictions, and other health measures have bad consequences on the productivity of many organizations. Whenever it is possible, many organizations are changed to manage their activities via online communications. However, this huge shift toward remote work expands the need for security solutions to withstand potential risks. Unfortunately, most of the existing authentication schemes are suffering from several weaknesses that need to be addressed.