A method performed by an authentication server for provisioning a user equipment (1), UE. The method comprises: obtaining a message authentication code, MAC, based on a provisioning key specific to the UE to the UE and a privacy key of a home network (3) of the UE, wherein the provisioning key is a shared secret between the authentication server (14) and the UE and the privacy key comprises a public key of the home network; and transmitting the privacy key and the MAC to the UE. Methods performed by a de-concealing server and the UE, respectively are also disclosed as well as authentication servers, de-concealing servers and UEs. A computer program and a memory circuitry (13) are also disclosed.