Paper 2013/646

Direct Chosen-Ciphertext Secure Attribute-Based Key Encapsulations without Random Oracles

Johannes Blömer and Gennadij Liske


We present a new technique to realize attribute-based encryption (ABE) schemes secure in the standard model against chosen-ciphertext attacks (CCA-secure). Our approach is to extend certain concrete chosen-plaintext secure (CPA-secure) ABE schemes to achieve more efficient constructions than the known generic constructions of CCA-secure ABE schemes. We restrict ourselves to the construction of attribute-based key encapsulation mechanisms (KEMs) and present two concrete CCA-secure schemes: a key-policy attribute-based KEM that is based on Goyal's key-policy ABE and a ciphertext-policy attribute-based KEM that is based on Waters' ciphertext-policy ABE. To achieve our goals, we use an appropriate hash function and need to extend the public parameters and the ciphertexts of the underlying CPA-secure encryption schemes only by a single group element. Moreover, we use the same hardness assumptions as the underlying CPA-secure encryption schemes.

Available format(s)
Public-key cryptography
Publication info
Preprint. MINOR revision.
attribute-based key encapsulation mechanismattribute-based encryptionchosen-ciphertext securitybilinear maps
Contact author(s)
gennadij liske @ upb de
2013-10-10: received
Short URL
Creative Commons Attribution


      author = {Johannes Blömer and Gennadij Liske},
      title = {Direct Chosen-Ciphertext Secure Attribute-Based Key Encapsulations without Random Oracles},
      howpublished = {Cryptology ePrint Archive, Paper 2013/646},
      year = {2013},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.