Advances in Cryptology – CRYPTO 2020
40th Annual International Cryptology Conference, CRYPTO 2020, Santa Barbara, CA, USA, August 17–21, 2020, Proceedings, Part II
Page
%P
-
Chapter and Conference Paper
Context Discovery and Commitment Attacks
A line of recent work has highlighted the importance of context commitment security, which asks that authenticated encryption with associated data (AEAD) schemes will not decrypt the same adversarially-chosen ...
-
Chapter and Conference Paper
A Fast and Simple Partially Oblivious PRF, with Applications
We build the first construction of a partially oblivious pseudorandom function (POPRF) that does not rely on bilinear pairings. Our construction can be viewed as combining elements of the 2HashDH OPRF of Jarec...
-
Chapter and Conference Paper
Authenticated Encryption with Key Identification
Authenticated encryption with associated data (AEAD) forms the core of much of symmetric cryptography, yet the standard techniques for modeling AEAD assume recipients have no ambiguity about what secret key to...
-
Book and Conference Proceedings
-
Book and Conference Proceedings
Advances in Cryptology – CRYPTO 2020
40th Annual International Cryptology Conference, CRYPTO 2020, Santa Barbara, CA, USA, August 17–21, 2020, Proceedings, Part III
-
Book and Conference Proceedings
Advances in Cryptology – CRYPTO 2020
40th Annual International Cryptology Conference, CRYPTO 2020, Santa Barbara, CA, USA, August 17–21, 2020, Proceedings, Part I
-
Chapter and Conference Paper
Asymmetric Message Franking: Content Moderation for Metadata-Private End-to-End Encryption
Content moderation is crucial for stop** abusive and harassing messages in online platforms. Existing moderation mechanisms, such as message franking, require platform providers to be able to associate user ...
-
Chapter and Conference Paper
Fast Message Franking: From Invisible Salamanders to Encryptment
Message franking enables cryptographically verifiable reporting of abusive messages in end-to-end encrypted messaging. Grubbs, Lu, and Ristenpart recently formalized the needed underlying primitive, what they ...
-
Chapter and Conference Paper
Modifying an Enciphering Scheme After Deployment
Assume that a symmetric encryption scheme has been deployed and used with a secret key. We later must change the encryption scheme in a way that preserves the ability to decrypt (a subset of) previously encryp...
-
Chapter and Conference Paper
Key Rotation for Authenticated Encryption
A common requirement in practice is to periodically rotate the keys used to encrypt stored data. Systems used by Amazon and Google do so using a hybrid encryption technique which is eminently practical but has...
-
Chapter and Conference Paper
Message Franking via Committing Authenticated Encryption
We initiate the study of message franking, recently introduced in Facebook’s end-to-end encrypted message system. It targets verifiable reporting of abusive messages to Facebook without compromising security g...
-
Chapter and Conference Paper
A New Distribution-Sensitive Secure Sketch and Popularity-Proportional Hashing
Motivated by typo correction in password authentication, we investigate cryptographic error-correction of secrets in settings where the distribution of secrets is a priori (approximately) known. We refer to th...
-
Chapter and Conference Paper
Honey Encryption Beyond Message Recovery Security
Juels and Ristenpart introduced honey encryption (HE) and showed how to achieve message recovery security even in the face of attacks that can exhaustively try all likely keys. This is important in contexts li...
-
Chapter and Conference Paper
A Formal Treatment of Backdoored Pseudorandom Generators
We provide a formal treatment of backdoored pseudorandom generators (PRGs). Here a saboteur chooses a PRG instance for which she knows a trapdoor that allows prediction of future (and possibly past) generator ...
-
Chapter and Conference Paper
Honey Encryption: Security Beyond the Brute-Force Bound
We introduce honey encryption (HE), a simple, general approach to encrypting messages using low min-entropy keys such as passwords. HE is designed to produce a ciphertext which, when decrypted with any of a numbe...
-
Chapter and Conference Paper
Message-Locked Encryption and Secure Deduplication
We formalize a new cryptographic primitive that we call Message-Locked Encryption (MLE), where the key under which encryption and decryption are performed is itself derived from the message. MLE provides a way...
-
Chapter and Conference Paper
The Mix-and-Cut Shuffle: Small-Domain Encryption Secure against N Queries
We provide a new shuffling algorithm, called Mix-and-Cut, that provides a provably-secure block cipher even for adversaries that can observe the encryption of all N = 2 n do...
-
Chapter and Conference Paper
Randomness Condensers for Efficiently Samplable, Seed-Dependent Sources
We initiate a study of randomness condensers for sources that are efficiently samplable but may depend on the seed of the condenser. That is, we seek functions Cond : {0,1} n ×{0...
-
Chapter and Conference Paper
To Hash or Not to Hash Again? (In)Differentiability Results for \(H^2\) and HMAC
We show that the second iterate \(H^2(M) = H(H(M))\) of a random oracle H cannot achieve strong security in the sense of indiff...
-
Chapter and Conference Paper
Multi-instance Security and Its Application to Password-Based Cryptography
This paper develops a theory of multi-instance (mi) security and applies it to provide the first proof-based support for the classical practice of salting in password-based cryptography. Mi-security comes into...
