Comment on "A Quantum Network System of QSS-QDC Using χ-Type Entangled States" Chin. Phys. Lett. 29 (2012) 050303

Two quantum secret sharing (QSS) protocols in a multiuser quantum direct communication (QDC) network system were put forward by Hong et al. Chin. Phys. Lett. 29 (2012) 050303. However, we find that either agent (Bob or Charlie) alone can obtain half the information about the sender's secret without collaboration with the other, which does not satisfy the security requirement of QSS. Moreover, the secret message sent by Alice in the second protocol can be eavesdropped on or its communication can be disturbed by the builder of quantum channels (Trent).