SLSong Liao

Song Liao

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

The organizations/institutes from the scholar's latest article


Song Liao has a total of 35 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Understanding User Acceptance of Privacy Labels: Barriers and Enhancements

    by Jingwen Yan, Mohammed Aldeen, Jalil Harris, Kellen Grossenbacher, Song Liao, Feng Luo, Long Cheng


  • Open Access

    AI-Cybersecurity Education Through Designing AI-based Cyberharassment Detection Lab

    by Ebuka Okpala, Nishant Vishwamitra, Keyan Guo, Song Liao, Long Cheng, Hongxin Hu, Xiaohong Yuan, Jeannette Wade, Sajad Khorsandroo

    Cyberharassment is a critical, socially relevant cybersecurity problem because of the adverse effects it can have on targeted groups or individuals. While progress has been made in understanding cyberharassment, its detection, attacks on artificial intelligence (AI) based cyberharassment systems, and the social problems in cyberharassment detectors, little has been done in designing experiential learning educational materials that engage students in this emerging social cybersecurity in the era of AI. Experiential learning opportunities are usually provided through capstone projects and engineering design courses in STEM programs such as computer science. While capstone projects are an excellent example of experiential learning, given the interdisciplinary nature of this emerging social cybersecurity problem, it can be challenging to use them to engage non-computing students without prior knowledge of AI. Because of this, we were motivated to develop a hands-on lab platform that provided experiential learning experiences to non-computing students with little or no background knowledge in AI. We also discussed the lessons learned in developing this lab for non-computing students. In this lab used by social science students at North Carolina A&T University across two semesters (spring and fall) in 2022, students are given a detailed lab manual and are to complete a set of well-detailed tasks. Through this process, students learn AI concepts and the application of AI for cyberharassment detection. Using pre-and post-surveys, we asked students to rate their knowledge or skills in AI and their understanding of the concepts learned. The results revealed that the students moderately understood the concepts of AI and cyberharassment.


  • Open Access

    Enhancing AI-Centered Social Cybersecurity Education through Learning Platform Design

    by Nishant Vishwamitra, Ebuka Okpala, Song Liao, Keyan Guo, Sandeep Shah, Hongxin Hu, Xiaohong Yuan, Long Cheng

    Artificial Intelligence (AI) technologies have become increasingly pervasive in our daily lives. Recent breakthroughs such as large language models (LLMs) are being increasingly used globally to enhance their work methods and boost productivity. However, the advent of these technologies has also brought forth new challenges in the critical area of social cybersecurity. While AI has broadened new frontiers in addressing social issues, such as cyberharassment and cyberbullying, it has also worsened existing social issues such as the generation of hateful content, bias, and demographic prejudices. Although the interplay between AI and social cybersecurity has gained much attention from the research community, very few educational materials have been designed to engage students by integrating AI and socially relevant cybersecurity through an interdisciplinary approach. In this paper, we present our newly designed open-learning platform, which can be used to meet the ever-increasing demand for advanced training in the intersection of AI and social cybersecurity. The designed platform, which consists of hands-on labs and education materials, incorporates the latest research results in AI-based social cybersecurity, such as cyberharassment detection, AI bias and prejudice, and adversarial attacks on AI-powered systems, are implemented using Jupyter Notebook, an open-source interactive computing platform for effective hands-on learning. Through a user study of 201 students from two universities, we demonstrate that students have a better understanding of AI-based social cybersecurity issues and mitigation after doing the labs, and they are enthusiastic about learning to use AI algorithms in addressing social cybersecurity challenges for social good.

  • Open Access

    A First Look at Security and Privacy Risks in the RapidAPI Ecosystem

    by Song Liao, Long Cheng, Xiapu Luo, Zheng Song, Haipeng Cai, Danfeng (Daphne) Yao, Hongxin Hu

    With the emergence of the open API ecosystem, third-party developers can publish their APIs on the API marketplace, significantly facilitating the development of cutting-edge features and services. The RapidAPI platform is currently the largest API marketplace and it provides over 40,000 APIs, which have been used by more than 4 million developers. However, such open API also raises security and privacy concerns associated with APIs hosted on the platform. In this work, we perform the first large-scale analysis of 32,089 APIs on the RapidAPI platform. By searching in the GitHub code and Android apps, we find that 3,533 RapidAPI keys, which are important and used in API request authorization, have been leaked in the wild. These keys can be exploited to launch various attacks, such as Resource Exhaustion Running, Theft of Service, Data Manipulation, and User Data Breach attacks. We also explore risks in API metadata that can be abused by adversaries. Due to the lack of a strict certification system, adversaries can manipulate the API metadata to perform typosquatting attacks on API URLs, impersonate other developers or renowned companies, and publish spamming APIs on the platform. Lastly, we analyze the privacy non-compliance of APIs and applications, e.g., Android apps, that call these APIs with data collection. We find that 1,709 APIs collect sensitive data and 94% of them dont provide a complete privacy policy. For the Android apps that call these APIs, 50% of them in our study have privacy non-compliance issues.


  • Open Access

    End-Users Know Best: Identifying Undesired Behavior of Alexa Skills Through User Review Analysis

    by Mohammed Aldeen, Jeffrey Young, Song Liao, Tsu-Yao Chang, Long Cheng, Haipeng Cai, Xiapu Luo, Hongxin Hu

    The Amazon Alexa marketplace has grown rapidly in recent years due to third-party developers creating large amounts of content and publishing directly to a skills store. Despite the growth of the Amazon Alexa skills store, there have been several reported security and usability concerns, which may not be identified during the vetting phase. However, user reviews can offer valuable insights into the security & privacy, quality, and usability of the skills. To better understand the effects of these problematic skills on end-users, we introduce ReviewTracker, a tool capable of discerning and classifying semantically negative user reviews to identify likely malicious, policy violating, or malfunctioning behavior on Alexa skills. ReviewTracker employs a pre-trained FastText classifier to identify different undesired skill behaviors. We collected over 700,000 user reviews spanning 6 years with more than 200,000 negative sentiment reviews. ReviewTracker was able to identify 17,820 reviews reporting violations related to Alexa policy requirements across 2,813 skills, and 131,855 reviews highlighting different types of user frustrations associated with 9,294 skills. In addition, we developed a dynamic skill testing framework using ChatGPT to conduct two distinct types of tests on Alexa skills: one using a software-based simulation for interaction to explore the actual behaviors of skills and another through actual voice commands to understand the potential factors causing discrepancies between intended skill functionalities and user experiences. Based on the number of the undesired skill behavior reviews, we tested the top identified problematic skills and detected more than 228 skills violating at least one policy requirement. Our results demonstrate that user reviews could serve as a valuable means to identify undesired skill behaviors.


  • Open Access

    Command Hijacking on Voice-Controlled IoT in Amazon Alexa Platform

    by Wenbo Ding, Song Liao, Long Cheng, Xianghang Mi, Ziming Zhao, Hongxin Hu

    Voice Personal Assistants (VPA) are becoming popular entry points to control connected devices in an IoT environment, e.g., by invoking Amazon Alexa voice-apps (called skills) to turn on/off lights through voice commands. Amazon Alexa platform allows third-party developers to build skills and publish them to marketplaces, which greatly extends the functionalities of VPA. Despite the many convenient features, there are increasing security and safety concerns about VPA-controlled IoT systems. Previous research demonstrated the prevalence of potentially malicious or problematic skills in the marketplace. However, existing works mainly focus on non-IoT skills (e.g., skills under the Kids and Health categories). The security and safety risks of IoT skills are largely under-explored. In this work, we discover new vulnerabilities in the Amazon Alexa platform, which allows malicious third-party developers to hijack Alexa's built-in voice commands to invoke malicious IoT skills. We present three new attacks hijacking Alexa's built-in IoT commands, including Command Invocation Confounding Attack, Custom Command Attack, and Command-Intent Hijacking Attack. We also find a vulnerability that allows arbitrary control of smart-home devices in the back-end code. We evaluate the success rate for each attack and prove that they can be used by malicious developers. In particular, we demonstrate that skills in the Connected Car category using Alexa's built-in intents can be hijacked by customized IoT skills. We also design and implement IoTSkillAnalyzer, a dynamic testing tool to examine IoT skills on the Alexa skills store. After analyzing 488 Alexa 3rd-party IoT skills using IoTSkillAnalyzer, we identified 52 skills with potential command hijacking attacks. We also found that 26 suspicious skills have hidden behaviors potentially caused by the Skill Back-end Code Manipulation vulnerability after they receive normal commands, such as failing to control devices, taking hidden actions, and providing wrong response information to users.


  • Open Access

    Understanding GDPR Non-Compliance in Privacy Policies of Alexa Skills in European Marketplaces

    by Song Liao, Mohammed Aldeen, Jingwen Yan, Long Cheng, Xiapu Luo, Haipeng Cai, Hongxin Hu

    Amazon Alexa is one of the largest Voice Personal Assistant (VPA) platforms and it allows third-party developers to publish their voice apps, named skills, to the Alexa skill store. To satisfy the needs of European users, Amazon Alexa has established multiple skill marketplaces in Europe and allows developers to publish skills in their native languages. Skills in European marketplaces are required to comply with GDPR (General Data Protection Regulation), which imposes strict obligations on data collection and processing. Skills that involve data collection should provide a privacy policy to disclose the data practice to users and meet GDPR requirements. In this work, we analyze the privacy policies of skills in European marketplaces, focusing on whether skills' privacy policies and data collection behaviors comply with GDPR. We collect a large-scale dataset that includes skills in all European marketplaces with privacy policies. To classify whether a sentence in a privacy policy provides GDPR information, we gather a labeled dataset including skills' privacy policy sentences and use it to train a BERT model. Then, we analyze the GDPR compliance of European skills. Using a dynamic testing tool based on ChatGPT, we check whether skills' privacy policies comply with GDPR and are consistent with the actual data collection behaviors. Surprisingly, we find that 67% of the privacy policies fail to comply with GDPR and don't provide necessary GDPR-related information. For 1,187 skills with data collection behaviors, we observe that 603 skills (50.8%) don't provide a complete privacy policy and 1,128 skills (95%) have GDPR non-compliance issues in their privacy policies. Meanwhile, we find that the GDPR has a positive influence on European privacy policies.


  • Open Access

    SkillScanner: Detecting Policy-Violating Voice Applications Through Static Analysis at the Development Phase

    by Song Liao, Long Cheng, Haipeng Cai, Linke Guo, Hongxin Hu

    The Amazon Alexa marketplace is the largest Voice Personal Assistant (VPA) platform with over 100,000 voice applications (i.e., skills) published to the skills store. In an effort to maintain the quality and trustworthiness of voice-apps, Amazon Alexa has implemented a set of policy requirements to be adhered to by third-party skill developers. However, recent works reveal the prevalence of policy-violating skills in the current skills store. To understand the causes of policy violations in skills, we first conduct a user study with 34 third-party skill developers focusing on whether they are aware of the various policy requirements defined by the Amazon Alexa platform. Our user study results show that there is a notable gap between VPA's policy requirements and skill developers' practices. As a result, it is inevitable that policy-violating skills will be published. To prevent the inflow of new policy-breaking skills to the skills store from the source, it is critical to identify potential policy violations at the development phase. In this work, we design and develop SkillScanner, an efficient static code analysis tool to facilitate third-party developers to detect policy violations early in the skill development lifecycle. To evaluate the performance of SkillScanner, we conducted an empirical study on 2,451 open source skills collected from GitHub. SkillScanner effectively identified 1,328 different policy violations from 786 skills. Our results suggest that 32% of these policy violations are introduced through code duplication (i.e., code copy and paste). In particular, we found that 42 skill code examples from potential Alexa's official accounts (e.g., ''alexa'' and ''alexa-samples'' on GitHub) contain policy violations, which lead to 81 policy violations in other skills due to the copy-pasted code snippets from these Alexa's code examples.