Sensitive and private information flows over smart home networks and it is therefore paramount that proper authentication be accomplished among the communicating entities. To achieve this, schemes based on techniques such as elliptic curve cryptography, public key cryptosystem, digital certificates, blockchains and bilinear pairing operations have been presented. However, these schemes either incur high computation and communication costs or do not consider most common attack scenarios in smart homes. In this paper, a protocol that leverages on lightweight XOR and hashing operations is developed. Security analysis using BAN logic shows that this protocol ensures secure mutual authentication among the communicating entities. It is also shown to be resilient against traceability, privacy, de-synchronization, stolen smart home device, session hijacking, man-in-the-middle, packet replay and insider attacks. In addition, it provides perfect forward key secrecy and exhibits average computation and communication overheads compared with its peers.