Recent technological developments in wireless and sensor networks have led to a paradigm shift in interacting with everyday objects, which nurtured the concept of Internet of Things (IoT). However, low-powered nature of IoT devices generally becomes a hindrance that makes them vulnerable to a wide array of attacks. Among these, the emergence of rogue devices is quickly becoming a major security concern. Rogue devices are malicious in nature which typically execute different kinds of cyberattacks by exploiting the weaknesses of access control schemes in IoT environments. Therefore, access control is one of the crucial aspects of an IoT ecosystem that defines an entry point for a device or a user in the network. This paper investigates this issue and presents an access control scheme by integrating an IoT network with blockchain technology, thereby arguing to replace the traditional centralized IoT-server architecture with a decentralized one. The blockchain is used with smart contracts to establish a secure platform for device registration. Due to this reason, the IoT devices are first required to register themselves and access the network via contracts thereafter. Moreover, the contracts host a device registry, the access control list, to grant or deny access to devices. This allows the proposed scheme to authorize registered devices only and block unregistered ones, which facilitates the mitigation of rogue devices. To demonstrate the feasibility and improvements of the proposed scheme, security analysis along with in-depth performance evaluation are conducted, where the obtained results indicate its applicability. A case study is also formulated with a comparative analysis that confirms the superior performance of the proposed scheme for low-powered IoT systems.