Many CAPTCHA proposals have shortcomings in their design or implementation that make themmuch weaker than intended. In this paper we study Captcha2, a commercial algorithm, as a means of showing typical flaws that make many CAPTCHAs prone to successful low-cost attacks. The attack we present makes no use of any AI techniques, not affecting the resilience of the original AI problem this CAPTCHA ...

Low Entropy Masking Schemes (LEMS) are a recent countermeasure against side-channel attacks. They aim at reducing the randomness requirements of masking schemes under certain (adversarial and implementation) conditions. Previous works have put forward the interest of this approach when such conditions are met. We complement these investigations by analyzing LEMS against adversaries and implemen...

We propose a novel approach for quantifying a system’s resistance to unknown-message side-channel attacks. The approach is based on a measure of the secret information that an attacker can extract from a system from a given number of side-channel measurements. We provide an algorithm to compute this measure, and we use it to analyze the resistance of hardware implementations of cryptographic al...

In this paper the secrecy problem in the cognitive state-dependent interference channel is considered. In this scenario we have a primary and a cognitive transmitter-receiver pairs. The cognitive transmitter has the message of the primary sender as side information. In addition, the state of the channel is known at the cognitive encoder. Hence, the cognitive encoder uses this side information t...

It's coming again, the new collection that this site has. To complete your curiosity, we offer the favorite power analysis side channel attacks the processor design level context book as the choice today. This is a book that will show you even new to old thing. Forget it; it will be right for you. Well, when you are really dying of power analysis side channel attacks the processor design level ...