Among other things, techniques are described for provisioning and authentication of devices in vehicles. In one aspect, a device in a vehicle establishes a communication session with a network server that manages provisioning of devices corresponding to an enterprise associated with the vehicle. The device receives instructions from the network server to generate cryptographic keys, and in response, generates a public and private key pair. The device sends, to the network server, a certificate signing request that includes the public key and an identifier of the device. In response, the device receives a digital security certificate for the device, and a security certificate of a signing certificate authority. The device authenticates the security certificate of the certificate authority using a known enterprise root certificate, and upon successful authentication, stores the device security certificate and the security certificate of the signing certificate authority.