Analysis on Hu et al.'s Identity-based Broadcast Encryption.
Xingwen Zhao, Fangguo Zhang · 2011
Analysis is given on Hu et al.’s efficient identity-based broadcast encryption (IBBE) scheme published in Journal of Computers, Vol. 5, No. 3, March 2010. Two major flaws are described. One is that valid group members outside the receiver set can still decrypt the ciphertext, which contradicts the authors ’ definition for IBBE. The other is that, given a valid private key, it is easy to generate private keys for other people without interacting with