In this abstract, we propose to exploit the particular features of hyperchaotic time-delay systems to overcome two of the main problems encountered in multiplexed chaotic encryption schemes: (1) the number of oscillators involved and (2) the complexity of the decryption process. We show the possibility to encrypt and decrypt multiple digital messages using just one hyperchaotic time-delay oscillator at the emission and at the reception. The encryption requires as many delayed feedback loops as messages to be sent. The decryption exploits chaos synchronization and a correlation-based technique to recover each message such that the complexity grows linearly with the number of users.