Computer Systems 4th Edition Warford Pdf Zip
Current fallback authentication mechanisms are unreliable (e.g., security questions are easy to guess) and need improvement. Social authentication shows promise as a novel form of fallback authentication. In this paper, we report the results of a four-week study that explored people's perceived willingness to use video chat as a form of social authentication. We investigated whether people's mood, location, and trust, and the presence of others affected perceived willingness to use video chat to authenticate. We found that participants who were alone, reported a more positive mood, and had more trust in others reported more willingness to use video chat as an authentication method. Participants also reported more willingness to help others to authenticate via video chat than to initiate a video chat authentication session themselves. Our results provide initial insights into human-computer interaction issues that could stem from using video chat as a fallback authentication method within a small social network of people (e.g., family members and close friends) who know each other well and trust each other.
computer systems 4th edition warford pdf zip
The Bluetooth standard is ubiquitously supported by computers, smartphones, and IoT devices. Due to its complexity, implementations require large codebases, which are prone to security vulnerabilities, such as the recently discovered BlueBorne and BadBluetooth attacks. While defined by the standard, most of the Bluetooth functionality, as defined by different Bluetooth profiles, is not required in the common usage scenarios.
Technology plays an increasingly salient role in facilitating intimate partner violence (IPV). Customer support at computer security companies are receiving cases that involve tech-enabled IPV but might not be well equipped to handle these cases. To assess customer support's existing practices and identify areas for improvement, we conducted five focus groups with professionals who work with IPV survivors (n=17). IPV professionals made numerous suggestions, such as using trauma-informed language, avoiding promises to solve problems, and making referrals to resources and support organizations. To evaluate the practicality of these suggestions, we conducted four focus groups with customer support practitioners (n=11). Support practitioners expressed interest in training agents for IPV cases, but mentioned challenges in identifying potential survivors and frontline agents' limited capacity to help. We conclude with recommendations for computer security companies to better address tech-enabled IPV through training support agents, tracking the prevalence of these cases, and establishing partnerships with IPV advocates.
Security architectures providing Trusted Execution Environments (TEEs) have been an appealing research subject for a wide range of computer systems, from low-end embedded devices to powerful cloud servers. The goal of these architectures is to protect sensitive services in isolated execution contexts, called enclaves. Unfortunately, existing TEE solutions suffer from significant design shortcomings. First, they follow a one-size-fits-all approach offering only a single enclave type, however, different services need flexible enclaves that can adjust to their demands. Second, they cannot efficiently support emerging applications (e.g., Machine Learning as a Service), which require secure channels to peripherals (e.g., accelerators), or the computational power of multiple cores. Third, their protection against cache sidechannel attacks is either an afterthought or impractical, i.e., no fine-grained mapping between cache resources and individual enclaves is provided.
Cybercrime is on the rise. Attacks by hackers, organized crime and nation-state adversaries are an economic threat for companies world-wide. Small and medium-sized enterprises (SMEs) have increasingly become victims of cyberattacks in recent years. SMEs often lack the awareness and resources to deploy extensive information security measures. However, the health of SMEs is critical for society: For example, in Germany, 38.8% of all employees work in SMEs, which contributed 31.9% of the German annual gross domestic product in 2018. Many guidelines and recommendations encourage companies to invest more into their information security measures. However, there is a lack of understanding of the adoption of security measures in SMEs, their risk perception with regards to cybercrime and their experiences with cyberattacks. To address this gap in research, we performed 5,000 computer-assisted telephone-interviews (CATIs) with representatives of SMEs in Germany. We report on their experiences with cybercrime, management of information security and risk perception. We present and discuss empirical results of the adoption of both technical and organizational security measures and risk awareness in SMEs. We find that many technical security measures and basic awareness have been deployed in the majority of companies. We uncover differences in reporting cybercrime incidences for SMEs based on their industry sector, company size and security awareness. We conclude our work with a discussion of recommendations for future research, industry and policy makers.
We find that framing a misconfiguration as a problem of legal compliance can increase remediation rates, especially when the notification is sent as a letter from a legal research group, achieving remediation rates of 76.3 % compared to 33.9 % for emails sent by computer science researchers warning about a privacy issue. Across all groups, 56.6 % of notified owners remediated the issue, compared to 9.2 % in the control group. In conclusion, we present factors that lead website owners to trust a notification, show what framing of the notification brings them into action, and how they can be supported in remediating the issue.
CAPTCHA is an effective mechanism for protecting computers from malicious bots. With the development of deep learning techniques, current mainstream text-based CAPTCHAs have been proven to be insecure. Therefore, a major effort has been directed toward developing image-based CAPTCHAs, and image-based visual reasoning is emerging as a new direction of such development. Recently, Tencent deployed the Visual Turing Test (VTT) CAPTCHA. This appears to have been the first application of a visual reasoning scheme. Subsequently, other CAPTCHA service providers (Geetest, NetEase, Dingxiang, etc.) have proposed their own visual reasoning schemes to defend against bots. It is, therefore, natural to ask a fundamental question: are visual reasoning CAPTCHAs as secure as their designers expect? This paper presents the first attempt to solve visual reasoning CAPTCHAs. We implemented a holistic attack and a modular attack, which achieved overall success rates of 67.3% and 88.0% on VTT CAPTCHA, respectively. The results show that visual reasoning CAPTCHAs are not as secure as anticipated; this latest effort to use novel, hard AI problems for CAPTCHAs has not yet succeeded. Based on the lessons we learned from our attacks, we also offer some guidelines for designing visual CAPTCHAs with better security.