In recent days, smart electronics have evolved into ubiquitous computing with connected interfaces such as self-driving automobiles with evolution in sensor network technology and artiﬁcial intelligence. Due to these advancements, new features are added into control area network in automobiles but the security and trust in these systems are still questionable because the improvement in automation is paving way for many potential cyber attacks. The closed systems such as in intra-vehicle conﬁguration, the control and command communication between electronic control units require custom architectures to support real time responses that integrate security and safety protocols. The centralized PKI depends on trusted third parties or a centralized server as certiﬁcation authority to share the public keys and generate digital certiﬁcates for asymmetric keys to provide authentication. The centralize CA can be a single point failure in the closed system. To address this problem, we propose a distributed key provisioning system using blockchain technology. We demonstrate the key provisioning scheme using Ethereum blockchain and smart contract for key storage and validation of the public key pair. The key storage and validation process involves all the nodes in the closed system and authenticates by traversing through their copy of blockchain and vote accordingly.