Biblio

This paper introduces a new type of attack on isolated, air-gapped workstations. Although air-gap computers have no wireless connectivity, we show that attackers can use the SATA cable as a wireless antenna to transfer radio signals at the 6 GHz frequency band. The Serial ATA (SATA) is a bus interface widely used in modern computers and connects the host bus to mass storage devices such as hard disk drives, optical drives, and solid-state drives. The prevalence of the SATA interface makes this attack highly available to attackers in a wide range of computer systems and IT environments. We discuss related work on this topic and provide technical background. We show the design of the transmitter and receiver and present the implementation of these components. We also demonstrate the attack on different computers and provide the evaluation. The results show that attackers can use the SATA cable to transfer a brief amount of sensitive information from highly secured, air-gap computers wirelessly to a nearby receiver. Furthermore, we show that the attack can operate from user mode, is effective even from inside a Virtual Machine (VM), and can successfully work with other running workloads in the background. Finally, we discuss defense and mitigation techniques for this new air-gap attack.

In order to protect user data while maintaining application functionality, encrypted databases can use specialized cryptography such as property-revealing encryption, which allows a property of the underlying plaintext values to be computed from the ciphertext. One example is deterministic encryption which ensures that the same plaintext encrypted under the same key will produce the same ciphertext. This technology enables clients to make queries on sensitive data hosted in a cloud server and has considerable potential to protect data. However, the security implications of deterministic encryption are not well understood. We provide a leakage analysis of deterministic encryption through the application of the framework of quantitative information flow. A key insight from this framework is that there is no single "right'' measure by which leakage can be quantified: information flow depends on the operational scenario and different operational scenarios require different leakage measures. We evaluate leakage under three operational scenarios, modeled using three different gain functions, under a variety of prior distributions in order to bring clarity to this problem.

We consider the situation, where an adversary may learn the ephemeral values used by the prover within an identification protocol, aiming to get the secret keys of the user, or just to impersonate the prover subsequently. Unfortunately, most classical cryptographic identification protocols are exposed to such attacks, which might be quite realistic in case of software implementations. According to a recent proposal from SECIT-2017, we regard a scheme to be secure, if a malicious verifier, allowed to set the prover's ephemerals in the query stage, cannot impersonate the prover later on. We focus on the Okamoto Identification Scheme (IS), and show how to make it immune to the threats described above. Via reduction to the GDH Problem, we provide security guarantees in case of insufficient control over the unit executing Okamoto identification protocol (the standard Okamoto protocol is insecure in this situation).

We develop a systematic approach for analyzing client-server applications that aim to hide sensitive user data from untrusted servers. We then apply it to Mylar, a framework that uses multi-key searchable encryption (MKSE) to build Web applications on top of encrypted data. We demonstrate that (1) the Popa-Zeldovich model for MKSE does not imply security against either passive or active attacks; (2) Mylar-based Web applications reveal users' data and queries to passive and active adversarial servers; and (3) Mylar is generically insecure against active attacks due to system design flaws. Our results show that the problem of securing client-server applications against actively malicious servers is challenging and still unsolved. We conclude with general lessons for the designers of systems that rely on property-preserving or searchable encryption to protect data from untrusted servers.

Although there has been much research on the leakage of sensitive data in Android applications, most of the existing research focus on how to detect the malware or adware that are intentionally collecting user privacy. There are not much research on analyzing the vulnerabilities of apps that may cause the leakage of privacy. In this paper, we present a vulnerability analyzing method which combines taint analysis and cryptography misuse detection. The four steps of this method are decompile, taint analysis, API call record, cryptography misuse analysis, all of which steps except taint analysis can be executed by the existing tools. We develop a prototype tool PW Exam to analysis how the passwords are handled and if the app is vulnerable to password leakage. Our experiment shows that a third of apps are vulnerable to leak the users' passwords.