SearcharxivSearch

arXiv subjects

Daisuke Miyamoto

Publications and source records attributed to Daisuke Miyamoto.

6 recordsLinked to original sources

An LLM Agent-based Framework for Whaling Countermeasures

With the spread of generative AI in recent years, attacks known as Whaling have become a serious threat. Whaling is a form of social engineering that targets important high-authority individuals within organizations and uses sophisticated fraudulent emails. In the context of Japanese universities, faculty members frequently hold positions that combine research leadership with authority within institutional workflows. This structural characteristic leads to the wide public disclosure of high-value information such as publications, grants, and detailed researcher profiles. Such extensive information exposure enables the construction of highly precise target profiles using generative AI. This raises concerns that Whaling attacks based on high-precision profiling by generative AI will become prevalent. In this study, we propose a Whaling countermeasure framework for university faculty members that constructs personalized defense profiles and uses large language model (LLM)-based agents. We design agents that (i) build vulnerability profiles for each target from publicly available information on faculty members, (ii) identify potential risk scenarios relevant to Whaling defense based on those profiles, (iii) construct defense profiles corresponding to the vulnerabilities and anticipated risks, and (iv) analyze Whaling emails using the defense profiles. Furthermore, we conduct a preliminary risk-assessment experiment. The results indicate that the proposed method can produce judgments accompanied by explanations of response policies that are consistent with the work context of faculty members who are Whaling targets. The findings also highlight practical challenges and considerations for future operational deployment and systematic evaluation.

cs.CR

mdx: A Cloud Platform for Supporting Data Science and Cross-Disciplinary Research Collaborations

The growing amount of data and advances in data science have created a need for a new kind of cloud platform that provides users with flexibility, strong security, and the ability to couple with supercomputers and edge devices through high-performance networks. We have built such a nation-wide cloud platform, called "mdx" to meet this need. The mdx platform's virtualization service, jointly operated by 9 national universities and 2 national research institutes in Japan, launched in 2021, and more features are in development. Currently mdx is used by researchers in a wide variety of domains, including materials informatics, geo-spatial information science, life science, astronomical science, economics, social science, and computer science. This paper provides an the overview of the mdx platform, details the motivation for its development, reports its current status, and outlines its future plans.

cs.LG

Classification of URL bitstreams using Bag of Bytes

Protecting users from accessing malicious web sites is one of the important management tasks for network operators. There are many open-source and commercial products to control web sites users can access. The most traditional approach is blacklist-based filtering. This mechanism is simple but not scalable, though there are some enhanced approaches utilizing fuzzy matching technologies. Other approaches try to use machine learning (ML) techniques by extracting features from URL strings. This approach can cover a wider area of Internet web sites, but finding good features requires deep knowledge of trends of web site design. Recently, another approach using deep learning (DL) has appeared. The DL approach will help to extract features automatically by investigating a lot of existing sample data. Using this technique, we can build a flexible filtering decision module by keep teaching the neural network module about recent trends, without any specific expert knowledge of the URL domain. In this paper, we apply a mechanical approach to generate feature vectors from URL strings. We implemented our approach and tested with realistic URL access history data taken from a research organization and data from the famous archive site of phishing site information, PhishTank.com. Our approach achieved 2~3% better accuracy compared to the existing DL-based approach.

cs.NI

Classifying DNS Servers based on Response Message Matrix using Machine Learning

Improperly configured domain name system (DNS) servers are sometimes used as packet reflectors as part of a DoS or DDoS attack. Detecting packets created as a result of this activity is logically possible by monitoring the DNS request and response traffic. Any response that does not have a corresponding request can be considered a reflected message; checking and tracking every DNS packet, however, is a non-trivial operation. In this paper, we propose a detection mechanism for DNS servers used as reflectors by using a DNS server feature matrix built from a small number of packets and a machine learning algorithm. The F1 score of bad DNS server detection was more than 0.9 when the test and training data are generated within the same day, and more than 0.7 for the data not used for the training and testing phase of the same day.

cs.NI

Attributes affecting user decision to adopt a Virtual Private Network (VPN) app

A Virtual Private Network (VPN) helps to mitigate security and privacy risks of data transmitting on unsecured network such as public Wi-Fi. However, despite awareness of public Wi-Fi risks becoming increasingly common, the use of VPN when using public Wi-Fi is low. To increase adoption, understanding factors driving user decision to adopt a VPN app is an important first step. This study is the first to achieve this objective using discrete choice experiments (DCEs) to elicit individual preferences of specific attributes of a VPN app. The experiments were run in the United Kingdom (UK) and Japan (JP). We first interviewed participants (15 UK, 17 JP) to identify common attributes of a VPN app which they considered important. The results were used to design and run a DCE in each country. Participants (149 UK, 94 JP) were shown a series of two hypothetical VPN apps, varying in features, and were asked to choose one which they preferred. Customer review rating, followed by price of a VPN app, significantly affected the decision to choose which VPN app to download and install. A change from a rating of 3 to 4-5 stars increased the probability of choosing an app by 33% in the UK and 14% in Japan. Unsurprisingly, price was a deterrent. Recommendations by friends, source of product reviews, and the presence of in-app ads also played a role but to a lesser extent. To actually use a VPN app, participants considered Internet speed, connection stability, battery level on mobile devices, and the presence of in-app ads as key drivers. Participants in the UK and in Japan prioritized these attributes differently, suggesting possible influences from cultural differences.

cs.CR

Application of a Self-Organizing State Space Model to the Leonid Meteor Storm in 2001

The Leonids show meteor storms in a period of 33 years, and known as one of the most active meteor showers. It has recently shown a meteor stream consisting of several narrow dust trails made by meteoroids ejected from a parent comet. Hence, an analysis of the temporal behavior of the meteor flux is important to study the structure of the trails. However, statistical inference for the count data is not an easy task, because of its Poisson characteristics. We carried out a wide-field video observation of the Leonid meteor storm in 2001. We formulated a state-of-the-art statistical analysis, which is called a self-organizing state space model, to infer the true behavior of the dust density of the trails properly from the meteor count data. {}From this analysis, we found that the trails have a fairly smooth spatial structure, with small and dense clumps that cause a temporal burst of meteor flux. We also proved that the time behavior (trend) of the fluxes of bright meteors and that of faint meteors are significantly different. In addition we comment on some other application of the self-organizing state-space model in fields related to astronomy and astrophysics.

astro-ph.IM