Biblio

Information security has become a crucial issue not only from the technical standpoint, but also from the managerial standpoint. The necessity for organizations to understand and manage cyber risk has led to the rise of a plethora of risk assessment methods and tools. These approaches are often difficult to interpret and complex to manage for organizations. In this paper, we propose a simple and quantitative method for the estimation of the likelihood of occurrence of a cyber incident. Our approach uses a generalized logistic function and a cumulative geometric distribution to combine the maturity and the complexity of the technical infrastructure of an organization with its attractiveness towards cyber criminals.

We consider a one-time digital signature scheme recently proposed by Persichetti and show that a successful key recovery attack can be mounted with limited complexity. The attack we propose exploits a single signature intercepted by the attacker, and relies on a statistical analysis performed over such a signature, followed by information set decoding. We assess the attack complexity and show that a full recovery of the secret key can be performed with a work factor that is far below the claimed security level. The efficiency of the attack is motivated by the sparsity of the signature, which leads to a significant information leakage about the secret key.