Why Textbook ElGamal and RSA Encryption Are Insecure
نویسندگان
چکیده
We present an attack on plain ElGamal and plain RSA encryption. The attack shows that without proper preprocessing of the plaintexts, both ElGamal and RSA encryption are fundamentally insecure. Namely, when one uses these systems to encrypt a (short) secret key of a symmetric cipher it is often possible to recover the secret key from the ciphertext. Our results demonstrate that preprocessing messages prior to encryption is an essential part of both systems.
منابع مشابه
Comparison of two Public Key Cryptosystems
Since the time public-key cryptography was introduced by Diffie andHellman in 1976, numerous public-key algorithms have been proposed. Some of thesealgorithms are insecure and the others that seem secure, many are impractical, eitherthey have too large keys or the cipher text they produce is much longer than theplaintext. This paper focuses on efficient implementation and analysis of two mostpo...
متن کاملSide-Channel Attacks on Textbook RSA and ElGamal Encryption
This paper describes very efficient attacks on plain RSA encryption as usually described in textbooks. These attacks exploit side channels caused by implementations that, during decryption, incorrectly make certain assumption on the size of message. We highlight different assumptions that are easily made when implementing plain RSA decryption and present corresponding attacks. These attacks mak...
متن کاملNew Computation Technique for Encryption and Decryption Based on Rsa and Elgamal Cryptosystems
Cryptography addresses the necessary elements for secure communication that involved privacy, confidentiality, key exchange, authentication, and non-repudiation. This paper proposed a new computation of encryption and decryption that was based on the computation of RSA and ElGamal Cryptosystems. The RSA is a public key encryption system that gets its security from the difficulty of factoring la...
متن کاملFinding Minimum Optimal Path Securely Using Homomorphic Encryption Schemes in Computer Networks
In this paper we find a secure routing protocol for computer networks, which finds minimum optimum path using homomorphic encryption schemes. We briefly look into the existing homomorphic encryption algorithms. We make use of ElGamal encryption, Elliptic Curve encryption and a privacy homomorphism, which exhibits the property of homomorphism in our new routing protocol. Elliptic curve exhibits ...
متن کاملEncoding-Free ElGamal Encryption Without Random Oracles
ElGamal encryption is the most extensively used alternative to RSA. Easily adaptable to many kinds of cryptographic groups, ElGamal encryption enjoys homomorphic properties while remaining semantically secure providing that the DDH assumption holds on the chosen group. Its practical use, unfortunately, is intricate: plaintexts have to be encoded into group elements before encryption, thereby re...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2000