Comment on "Quantum secret sharing based on reusable   Greenberger-Horne-Zeilinger states as secure carriers" [Phys. Rev. A 67,   044302 (2003)]
  In a recent paper [S. Bagherinezhad and V. Karimipour, Phys. Rev. A 67, 044302 (2003)], a quantum secret sharing protocol based on reusable GHZ states was proposed. However, in this Comment, it is shown that this protocol is insecure if Eve employs a special strategy to attack. 
Fei Gao, Fenzhuo Guo, Qiaoyan Wen, Fuchen Zhu