Title
Cryptanalysis and Improvement of a Pairing-Free Certificateless Signature Scheme
Abstract
Certificateless signature (CLS) schemes aim to eliminate the need of certificates in traditional public-key signature schemes and also to resolve the inherent keyescrow problem of identity-based signature schemes. There are a vast number of secure CLS schemes in the literature; however, the usage of map-to-point hash functions and bilinear pairings in their constructions makes them less efficient to be applicable in many real-world applications. Recently, Karati et al. proposed an elliptic curve based CLS scheme in which there exists neither any bilinear pairing nor any map-to-points hash function. The authors claimed that the proposed CLS scheme is existentially unforgeable against both types of adversaries considered in certificateless cryptography. However, in this paper, we show that this claim is wrong and a type-1 adversary of certificateless cryptography can forge the signature of any signer on any message of his choice in this scheme. We further slightly modify Karati et al.'s scheme in order to make it secure in the standard security model of a CLS scheme. Meanwhile, the proposed improved scheme preserves all the efficiency properties of Karati et al.'s scheme.
Year
DOI
Venue
2018
10.1109/ISCISC.2018.8546984
2018 15th International ISC (Iranian Society of Cryptology) Conference on Information Security and Cryptology (ISCISC)
Keywords
Field
DocType
Digital signature,Certificateless cryptography,Elliptic curve,Forgeability,Improvement
Computer science,Computer security,Cryptanalysis,Theoretical computer science,Pairing,Certificateless cryptography,Hash function,Elliptic curve cryptography,Computer security model,Elliptic curve,Bilinear interpolation
Conference
ISSN
ISBN
Citations 
2475-2363
978-1-5386-7583-0
0
PageRank 
References 
Authors
0.34
14
2
Name
Order
Citations
PageRank
Nasrollah Pakniat1235.55
Behnam Abasi Vanda200.34