On the efficiency of a general attack against the MOBS cryptosystem
This work addresses security concerns for cryptographers by showing that MOBS is resistant to a known attack, though it is incremental as it focuses on a specific instance.
The paper investigates the MOBS cryptosystem, a variant of the semidirect key exchange protocol, and finds that the telescoping equality attack is inefficient due to having too many solutions, making it impractical for real-world use.
All instances of the semidirect key exchange protocol, a generalisation of the famous Diffie-Hellman key exchange protocol, satisfy the so-called "telescoping equality"; in some cases, this equality has been used to construct an attack. In this report we present computational evidence suggesting that an instance of the scheme called `MOBS' is an example of a scheme where the telescoping equality has too many solutions to be a practically viable means to conduct an attack.