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Security of Encryption Schemes in Weakened Random Oracle Models [chapter]

Akinori Kawachi, Akira Numayama, Keisuke Tanaka, Keita Xagawa
2010 Lecture Notes in Computer Science  
Liskov proposed several weakened versions of the random oracle model, called weakened random oracle models (WROMs), to capture the vulnerability of ideal compression functions, which are expected to have  ...  In this paper, we investigate whether public-key encryption schemes in the random oracle model essentially require the standard security of hash functions by the WROMs.  ...  This research was supported in part by NTT Information Sharing Platform Laboratories, JSPS Global COE program "Computationalism as Foundation for the Sciences," KAKENHI 18300002, KAKENHI 19-55201, and  ... 
doi:10.1007/978-3-642-13013-7_24 fatcat:qnkkho7bgfcrbdkzvsygbxvk54

A Unified Approach to Idealized Model Separations via Indistinguishability Obfuscation [chapter]

Matthew D. Green, Jonathan Katz, Alex J. Malozemoff, Hong-Sheng Zhou
2016 Lecture Notes in Computer Science  
Thus, this leaves open the possibility that some cryptographic schemes, such as bit-encryption, are still sound in the random oracle model.  ...  It is well known that the random oracle model is not sound in the sense that there exist cryptographic systems that are secure in the random oracle model but when instantiated by any family of hash functions  ...  Acknowledgments The authors would like to thank Brent Waters and Susan Hohenberger for helpful conversations during the course of this work. Matthew  ... 
doi:10.1007/978-3-319-44618-9_31 fatcat:4hh3ho73hnfb7gyjmc4fbgjye4

A survey of certificateless encryption schemes and security models

Alexander W. Dent
2008 International Journal of Information Security  
Lastly, we discuss the difficulties in proving the security of a certificateless scheme in the standard model, and propose possible ways of finding a solution to this problem.  ...  We also survey all known certificateless encryption schemes and point out that there are no known certificateless encryption schemes that achieve the highest levels of security without using the random  ...  Acknowledgements The author is indebted to the provable security working group in ECRYPT's AZTEC lab for their help in discussing the topics of this paper.  ... 
doi:10.1007/s10207-008-0055-0 fatcat:5f26gjykwfex3bq7p2dfhp7hke

New Public Key Cryptosystems Based on the Dependent-RSA Problems [chapter]

David Pointcheval
1999 Lecture Notes in Computer Science  
Then, two variants are derived with improved security properties, namely against adaptive chosen-ciphertext attacks, in the random oracle model.  ...  They are next used to provide new encryption schemes which are both secure and efficient. More precisely, the main scheme is proven semantically secure in the standard model.  ...  In spite of a recent paper [6] making people to be careful with the random oracle model, the security of OAEP has been widely agreed.  ... 
doi:10.1007/3-540-48910-x_17 fatcat:6apm6uyfxfcchlmyuiacl6tfva

Relations between semantic security and anonymity in identity-based encryption

Javier Herranz, Fabien Laguillaumie, Carla Ràfols
2011 Information Processing Letters  
In this paper we investigate the relations between these selective and adaptive notions, for identity-based encryption schemes enjoying at the same time some security and anonymity properties.  ...  Semantic security and anonymity are the two main properties that an identity-based encryption scheme can satisfy.  ...  The work of Javier Herranz is supported by a Ramón y Cajal grant, partially funded by the European Social Fund (ESF) of the Spanish MICINN Ministry.  ... 
doi:10.1016/j.ipl.2011.02.002 fatcat:h5puogp2yfaglmjwszn4hy5lqu

Using Hash Functions as a Hedge against Chosen Ciphertext Attack [chapter]

Victor Shoup
2000 Lecture Notes in Computer Science  
is true by providing a proof of security in the random oracle model. * To appear, Proc.  ...  In this paper we present a practical hybrid scheme that is just as efficient as the scheme of of Cramer and Shoup; indeed, the scheme is slightly more efficient than the one originally presented by Cramer  ...  of a practical cryptographic scheme of any kind-except in the random oracle model.  ... 
doi:10.1007/3-540-45539-6_19 fatcat:qpfkgh6kpfegvhdwcdisxbdoza

Functional Encryption: Definitions and Challenges [chapter]

Dan Boneh, Amit Sahai, Brent Waters
2011 Lecture Notes in Computer Science  
We then present a natural simulation-based definition and show that it (provably) cannot be satisfied in the standard model, but can be satisfied in the random oracle model.  ...  We initiate the formal study of functional encryption by giving precise definitions of the concept and its security.  ...  These first schemes were proven secure in the random oracle model.  ... 
doi:10.1007/978-3-642-19571-6_16 fatcat:iiz6j7bhezfifglqjtwbi7rwom

On the (Im)possibility of aggregate message authentication codes

Aldar C-F. Chan, Claude Castelluccia
2008 2008 IEEE International Symposium on Information Theory  
It is shown that a straightforward and intuitive refinement of the MAC security model (for the data aggregation setting) is not achievable.  ...  End-to-end privacy and aggregate integrity are the two main goals of secure data aggregation.  ...  ACKNOWLEDGMENT The first author would like to acknowledge the financial support provided by the Ministry of Education, Singapore through the Lee Kuan Yew Postdoctoral Fellowship and AcRF research grant  ... 
doi:10.1109/isit.2008.4594983 dblp:conf/isit/ChanC08 fatcat:mkfwcbb23vbvpppiw2asc5etoi

Protecting against key-exposure: strongly key-insulated encryption with optimal threshold

Mihir Bellare, Adriana Palacio
2005 Applicable Algebra in Engineering, Communication and Computing  
We take its realization further towards practice by presenting simple new schemes that provide benefits over previous ones in terms of scalability, performance and security.  ...  Our first contribution is a simple, practical, scalable scheme called SKIE-OT that achieves the best possible security in their framework.  ...  It is shown in [10] that this security is achieved in the random oracle model under the bilinear DH assumption. Our SKIE-OT scheme.  ... 
doi:10.1007/s00200-005-0183-y fatcat:4nx5kp6vbffx5ngyrbrivmtfyy

Public-Key Encryption Secure Against Related Randomness Attacks for Improved End-to-End Security of Cloud/Edge Computing

Pengtao Liu
2020 IEEE Access  
This paper proposes some methods of constructing secure public-key encryption scheme against related randomness attacks, i.e.  ...  Public-key encryption is often used to protect data security/privacy and secure communication in scenarios of cloud computing and edge computing.  ...  In this paper, we focus on constructing secure PKE schemes in the model of related randomness attacks.  ... 
doi:10.1109/access.2020.2967457 fatcat:lekze4p3cve55nve3fu2bcfchm

Random-Oracle Uninstantiability from Indistinguishability Obfuscation [chapter]

Christina Brzuska, Pooya Farshim, Arno Mittelbach
2015 Lecture Notes in Computer Science  
Assuming the existence of indistinguishability obfuscation (iO), we show that a number of prominent transformations in the random-oracle model are uninstantiable in the standard model.  ...  Our results call for a re-assessment of scheme design in the random-oracle model and highlight the need for new transforms that do not suffer from iO-based attacks.  ...  Israel Ministry of  ... 
doi:10.1007/978-3-662-46497-7_17 fatcat:x4kztrpkyrgm7clzws2z26oic4

Soundness of Formal Encryption in the Presence of Key-Cycles [chapter]

Pedro Adão, Gergei Bana, Jonathan Herzog, Andre Scedrov
2005 Lecture Notes in Computer Science  
We demonstrate that an encryption scheme provides soundness in the presence of key-cycles if it satisfies the recently-introduced notion of key-dependent message (KDM) security.  ...  An encryption scheme provides soundness for indistinguishability if, when mapping formal messages into the computational model, equivalent formal messages are mapped to indistinguishable computational  ...  Some of our joint work was done during the Protocol eXchange meetings. We thank S. Pinsky, E. Zieglar, and G. Dinolt for organizing the meetings and  ... 
doi:10.1007/11555827_22 fatcat:uq7a3froj5cjtjtnftbvwhkkjq

Efficient Designated Confirmer Signatures Without Random Oracles or General Zero-Knowledge Proofs [chapter]

Craig Gentry, David Molnar, Zulfikar Ramzan
2005 Lecture Notes in Computer Science  
Most prior designated confirmer signature schemes either prove security in the random oracle model (ROM) or use general zeroknowledge proofs for NP statements (making them impractical).  ...  In this paper, we provide an alternate generic transformation to convert any signature scheme into a designated confirmer signature scheme, without adding random oracles.  ...  Other than the Okamoto scheme just mentioned, the remaining schemes all have security proofs in the random oracle model [2] .  ... 
doi:10.1007/11593447_36 fatcat:ae2l5onoprcopo7oyif3r35uyi

Construction for Searchable Encryption with Strong Security Guarantees

István Vajda
2019 International Journal of Computer Network and Information Security  
Our construction is secure in the standard model of computation assuming bilinear groups with the widely used Symmetric eXternal Diffie Hellmann (SXDH) assumption.  ...  Attacks via searching for patterns in the database is prevented by randomized keyword encryption and trapdoor generation.  ...  In [12] proofs are given in the non-standard model of computation (in the random oracle model), while we work in the standard model.  ... 
doi:10.5815/ijcnis.2019.05.01 fatcat:s74ai52jfjct3d6g4bwaokr6ly

Key Wrapping with a Fixed Permutation [chapter]

Dmitry Khovratovich
2014 Lecture Notes in Computer Science  
We also present a simple proof of security within the concept of Deterministic Authenticated Encryption (DAE) introduced by Rogaway and Shrimpton.  ...  Our scheme easily delivers the security level of 128 bits or higher with the master key of the same length.  ...  However, the performance is gained at the cost of weakening the model.  ... 
doi:10.1007/978-3-319-04852-9_25 fatcat:4ua33abutjg6hbyth5lw5m3aya
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