2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/102491We show an eavesdropping scheme, by which the eavesdropper can achieve the full information of the key against the protocol [Kye et al., PRL 95 040501 (2005)] with a probability of unity and will not be discovered by the the legitimate users, even in the case that they have the perfect single-photon source and the loseless channel.2 pages 0 figures, comments are welcome!Quantum Physicstext