CCA Updatable Encryption Against Malicious Re-encryption Attacks
CCA Updatable Encryption Against Malicious Re-encryption Attacks
复制标题
针对恶意重新加密攻击的 CCA 可更新加密
DOI:
10.1007/978-3-030-64840-4_20
复制
发表时间:
2020
期刊:
影响因子:
--
通讯作者:
Tang, Qiang
中科院分区:
文献类型:
--
作者:
Chen, Long;Li, Yanan;Tang, Qiang
Updatable encryption (UE) is an attractive primitive, which allows the secret key of the outsourced encrypted data to be updated to a fresh one periodically. Several elegant works exist studying various security properties. We notice several major issues in existing security models of (ciphertext dependent) updatable encryption, in particular, integrity and CCA security. The adversary in the models is only allowed to request the server to re-encrypthonestlygenerated ciphertext, while in practice, an attacker could try to inject arbitrary ciphertexts into the server as she wishes. Those malformed ciphertext could be updated and leveraged by the adversary and cause serious security issues.In this paper, we fill the gap and strengthen the security definitions in multiple aspects: most importantly our integrity and CCA security models remove the restriction in previous models and achieve standard notions of integrity and CCA security in the setting of updatable encryption. Along the way, we refine the security model to capture post-compromise security and enhance the re-encryption indistinguishability to the CCA style. Guided by the new models, we provide a novel constructionReCrypt, which satisfies our strengthened security definitions. The technical building block of homomorphic hash from a group may be of independent interests. We also study the relations among security notions; and a bit surprisingly, the folklore result in authenticated encryption that IND-CPA plus ciphertext integrity imply IND-CCA security doesnothold for ciphertext dependent updatable encryption.
DOI:
10.1016/j.clsr.2008.07.001
发表时间:
2008
期刊:
Banking & Financial Institutions
影响因子:
--
作者:
E. Morse;Vasant Raval
通讯作者:
Vasant Raval
DOI:
10.1007/978-3-030-17653-2_3
发表时间:
2019
期刊:
IACR Cryptol. ePrint Arch.
影响因子:
--
作者:
M. Klooß;A. Lehmann;A. Rupp
通讯作者:
A. Rupp
DOI:
--
发表时间:
2018
期刊:
IACR Cryptology ePrint Archive
影响因子:
--
作者:
Anja Lehmann;Björn Tackmann
通讯作者:
Björn Tackmann