Insufficient properties of image encryption algorithms

TL;DR

This paper critically examines a recent image encryption scheme, demonstrating its insecurity and highlighting that statistical properties alone are insufficient for security evaluation.

Contribution

It introduces the Deliberately Weak Cipher to show that statistical analysis cannot replace comprehensive security assessment.

Findings

The analyzed scheme is insecure.

Statistical properties are insufficient for security evaluation.

A weak cipher with good statistical properties can still be vulnerable.

Abstract

We analyze the security of recently proposed image encryption scheme [1]. We show that the scheme is insecure and the methods used to evaluate its security are insufficient. By designing the Deliberately Weak Cipher, a completely vulnerable cipher with good statistical properties, we illustrate our main point -- a solid analysis cannot be replaced by some selected set of statistical properties.