CryptoEval: Evaluating the Risk of Cryptographic Misuses in Android Apps with Data-Flow Analysis

The misunderstanding and incorrect configurations of cryptographic primitives have exposed severe security vulnerabilities to attackers. Due to the pervasiveness and diversity of cryptographic misuses, a comprehensive and accurate understanding of how cryptographic misuses can undermine the security of an Android app is critical to the subsequent mitigation strategies but also challenging. Although various approaches have been proposed to detect cryptographic misuses in Android apps, seldom studies have focused on estimating the security risks introduced by cryptographic misuses. To address this problem, we present an extensible framework for deciding the threat level of cryptographic misuses in Android apps. Firstly, we propose a unified specification for representing cryptographic misuses to make our framework extensible and develop adapters to unify the detection results of the state-of-the-art cryptographic misuse detectors, resulting in an adapter-based detection toolchain for a more comprehensive list of cryptographic misuses. Secondly, we employ a misuse-originating data-flow analysis to connect each cryptographic misuse to a set of data-flow sinks in an app, based on which we propose a quantitative data-flow-driven metric for assessing the overall risk of the app introduced by cryptographic misuses. To make the per-app assessment more useful in the app vetting at the app-store level, we apply unsupervised learning to predict and classify the top risky threats, to guide more efficient subsequent mitigations. In the experiments on an instantiated implementation of the framework, we evaluate the accuracy of our detection and the effect of data-flow-driven risk assessment of our framework. Our empirical study on over 40,000 apps as well as the analysis of popular apps reveals important security observations on the real threats of cryptographic misuses in Android apps

To Fix or Not to Fix: A Critical Study of Crypto-misuses in the Wild

Recent studies have revealed that 87 % to 96 % of the Android apps using cryptographic APIs have a misuse which may cause security vulnerabilities. As previous studies did not conduct a qualitative examination of the validity and severity of the findings, our objective was to understand the findings in more depth. We analyzed a set of 936 open-source Java applications for cryptographic misuses. Our study reveals that 88.10 % of the analyzed applications fail to use cryptographic APIs securely. Through our manual analysis of a random sample, we gained new insights into effective false positives. For example, every fourth misuse of the frequently misused JCA class MessageDigest is an effective false positive due to its occurrence in a non-security context. As we wanted to gain deeper insights into the security implications of these misuses, we created an extensive vulnerability model for cryptographic API misuses. Our model includes previously undiscussed attacks in the context of cryptographic APIs such as DoS attacks. This model reveals that nearly half of the misuses are of high severity, e.g., hard-coded credentials and potential Man-in-the-Middle attacks.Comment: 8 pages, published in 2022 IEEE International Conference on Trust, Security and Privacy in Computing and Communications (TrustCom), December 09-11, 2022, Wuhan, Chin

Improving Android app security and privacy with developers

Existing research has uncovered many security vulnerabilities in Android applications (apps) caused by inexperienced, and unmotivated developers. Especially, the lack of tool support makes it hard for developers to avoid common security and privacy problems in Android apps. As a result, this leads to apps with security vulnerability that exposes end users to a multitude of attacks. This thesis presents a line of work that studies and supports Android developers in writing more secure code. We first studied to which extent tool support can help developers in creating more secure applications. To this end, we developed and evaluated an Android Studio extension that identifies common security problems of Android apps, and provides developers suggestions to more secure alternatives. Subsequently, we focused on the issue of outdated third-party libraries in apps which also is the root cause for a variety of security vulnerabilities. Therefore, we analyzed all popular 3rd party libraries in the Android ecosystem, and provided developers feedback and guidance in the form of tool support in their development environment to fix such security problems. In the second part of this thesis, we empirically studied and measured the impact of user reviews on app security and privacy evolution. Thus, we built a review classifier to identify security and privacy related reviews and performed regression analysis to measure their impact on the evolution of security and privacy in Android apps. Based on our results we proposed several suggestions to improve the security and privacy of Android apps by leveraging user feedbacks to create incentives for developers to improve their apps toward better versions.Die bisherige Forschung zeigt eine Vielzahl von Sicherheitslücken in Android-Applikationen auf, welche sich auf unerfahrene und unmotivierte Entwickler zurückführen lassen. Insbesondere ein Mangel an Unterstützung durch Tools erschwert es den Entwicklern, häufig auftretende Sicherheits- und Datenschutzprobleme in Android Apps zu vermeiden. Als Folge führt dies zu Apps mit Sicherheitsschwachstellen, die Benutzer einer Vielzahl von Angriffen aussetzen. Diese Dissertation präsentiert eine Reihe von Forschungsarbeiten, die Android-Entwickler bei der Entwicklung von sichereren Apps untersucht und unterstützt. In einem ersten Schritt untersuchten wir, inwieweit die Tool-Unterstützung Entwicklern beim Schreiben von sicherem Code helfen kann. Zu diesem Zweck entwickelten und evaluierten wir eine Android Studio-Erweiterung, die gängige Sicherheitsprobleme von Android-Apps identifiziert und Entwicklern Vorschläge für sicherere Alternativen bietet. Daran anknüpfend, konzentrierten wir uns auf das Problem veralteter Bibliotheken von Drittanbietern in Apps, die ebenfalls häufig die Ursache von Sicherheitslücken sein können. Hierzu analysierten wir alle gängigen 3rd-Party-Bibliotheken im Android-Ökosystem und gaben den Entwicklern Feedback und Anleitung in Form von Tool-Unterstützung in ihrer Entwicklungsumgebung, um solche Sicherheitsprobleme zu beheben. Im zweiten Teil dieser Dissertation untersuchten wir empirisch die Auswirkungen von Benutzer-Reviews im Android Appstore auf die Entwicklung der Sicherheit und des Datenschutzes von Apps. Zu diesem Zweck entwickelten wir einen Review-Klassifikator, welcher in der Lage ist sicherheits- und datenschutzbezogene Reviews zu identifizieren. Nachfolgend untersuchten wir den Einfluss solcher Reviews auf die Entwicklung der Sicherheit und des Datenschutzes in Android-Apps mithilfe einer Regressionsanalyse. Basierend auf unseren Ergebnissen präsentieren wir verschiedene Vorschläge zur Verbesserung der Sicherheit und des Datenschutzes von Android-Apps, welche die Reviews der Benutzer zur Schaffung von Anreizen für Entwickler nutzen

A Case Study of Mobile Health Applications: The OWASP Risk of Insufficient Cryptography

Mobile devices are being deployed rapidly for both private and professional reasons. One area of that has been growing is in releasing healthcare applications into the mobile marketplaces for health management. These applications help individuals track their own biorhythms and contain sensitive information. This case study examines the source code of mobile applications released to GitHub for the Risk of Insufficient Cryptography in the Top Ten Mobile Open Web Application Security Project risks. We first develop and justify a mobile OWASP Cryptographic knowledgegraph for detecting security weaknesses specific to mobile applications which can be extended to other domains involving cryptography. We then analyze the source code of 203 open source healthcare mobile applications and report on their usage of cryptography in the applications. Our findings show that none of the open source healthcare applications correctly applied cryptography in all elements of their applications. As humans adopt healthcare applications for managing their health routines, it is essential that they consider the privacy and security risks they are accepting when sharing their data. Furthermore, many open source applications and developers have certain environmental parameters which do not mandate adherence to regulations. In addition to creating new free tools for security risk identifications during software development such as standalone or compiler-embedded, the article suggests awareness and training modules for developers prior to marketplace software release

Measuring and characterizing weak RSA keys across PKI ecosystem

The insecurities of public-key infrastructure on the Internet have been the focus of research for over a decade. The extensive presence of broken, weak, and vulnerable cryptographic keys has been repeatedly emphasized by many studies. Analyzing the security implications of cryptographic keys' vulnerabilities, several studies noted the presence of public key reuse. While the phenomenon of private key sharing was extensively studied, the prevalence of public key sharing on the Internet remains largely unknown. This work performs a large-scale analysis of public key reuse within the PKI ecosystem. This study investigates the presence and distribution of duplicate X.509 certificates and reused RSA public keys across a large collection containing over 315 million certificates and over 13 million SSH keys collected over several years. This work analyzes the cryptographic weaknesses of duplicate certificates and reused keys and investigates the reasons and sources of reuse. The results reveal that certificate and key sharing are common and persistent. The findings show over 10 million certificates and 17 million public keys are reused across time and shared between the collections. Observations show keys with non-compliant cryptographic elements stay available for an extended period of time. The widespread adoption of Android apps has led to increasing concerns about the reuse of digital certificates. Android app developers frequently depend on digital certificates to sign their applications, and users place their trust in an app when they recognize the owner provided by the same certificate. Although the presence of cryptographic misuse has been acknowledged by several studies, its extent and characteristics are not well understood. This study performs a detailed analysis of code-signing certificate reuse across the Android ecosystem and malware binaries on a collection of over 19 million certificates and over 9 million keys extracted from PE files and Android applications collected over several years. The results reveal that despite the growing nature of the Android ecosystem, the misuse of cryptographic elements is common and persistent. The findings uncover several issues and enable us to provide a series of applicable solutions to the seen security flaws

Holistic security 4.0

The future computer climate will represent an ever more aligned world of integrating technologies, affecting consumer, business and industry sectors. The vision was first outlined in the Industry 4.0 conception. The elements which comprise smart systems or embedded devices have been investigated to determine the technological climate. The emerging technologies revolve around core concepts, and specifically in this project, the uses of Internet of Things (IoT), Industrial Internet of Things (IIoT) and Internet of Everything (IoE). The application of bare metal and logical technology qualities are put under the microscope to provide an effective blue print of the technological field. The systems and governance surrounding smart systems are also examined. Such an approach helps to explain the beneficial or negative elements of smart devices. Consequently, this ensures a comprehensive review of standards, laws, policy and guidance to enable security and cybersecurity of the 4.0 systems

“I Don’t Know Too Much About It”: On the Security Mindsets of Computer Science Students

The security attitudes and approaches of software developers have a large impact on the software they produce, yet we know very little about how and when these views are constructed. This paper investigates the security and privacy (S&P) perceptions, experiences, and practices of current Computer Science students at the graduate and undergraduate level using semi-structured interviews. We find that the attitudes of students already match many of those that have been observed in professional level developers. Students have a range of hacker and attack mindsets, lack of experience with security APIs, a mixed view of who is in charge of S&P in the software life cycle, and a tendency to trust other peoples' code as a convenient approach to rapidly build software. We discuss the impact of our results on both curriculum development and support for professional developers