• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.33 no.3
• /
• pp.471-485
• /
• 2023

Recently, due to the nature of blockchain that guarantees users' anonymity, more and more cases are being exploited for crimes such as illegal transactions. However, cryptocurrency is protected in cryptocurrency wallets, making it difficult to recover criminal funds. Therefore, this study acquires artifacts from the data and memory area of a local PC based on user behavior from four browser extension wallets (Metamask, Binance, Phantom, and Kaikas) to track and retrieve cryptocurrencies used in crime, and analyzes how to use them from a digital forensics perspective. As a result of the analysis, the type of wallet and cryptocurrency used by the suspect was confirmed through the API name obtained from the browser's cache data, and the URL and wallet address used for the remittance transaction were obtained. We also identified Client IDs that could identify devices used in cookie data, and confirmed that mnemonic code could be obtained from memory. Additionally, we propose an algorithm to measure the persistence of obtainable mnemonic code and automate acquisition.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.6
• /
• pp.281-288
• /
• 2014

QR code (abbreviated from Quick Response Code) is code system that is strong in against to apply image processing techniques (skew, warp, blur, and rotate) as QR codes can store several hundred times the amount of information carried by ordinary bar codes. For this reason, QR code is used in various fields, e.g., air ticket (boarding control system), food(vegetables, meat etc.) tracking system, contact lenses management, prescription management, patient wrist band (patient management) etc. In this paper, we proposed reversible data hiding for binary images. A reversible data hiding algorithm, which can recover the original image without any distortion from the marked (stego) image after the hidden data have been extracted, because it is possible to use various kinds of purposes. QR code can be used to generate by anyone so it can be easily used for crime. In order to prevent crimes related QR code, reversible data hiding can confirm if QR code is counterfeit or not as including authentication information. In this paper, we proved proposed method as experiments.

• The Journal of the Korea Contents Association
• /
• v.5 no.5
• /
• pp.85-91
• /
• 2005

Recently, home network system is providing more various services as home robot applied. A home robot not only basically controls home device but also services prevention of crimes, prevention of disasters through home monitoring and various entertainments while it navigates the autonomously based home network system. However, for the existing home robot to it is not easy to install all functions because the size of robot device becomes larger and the management of contents and applications executed becomes uneasy and has difficulties in adding new functions. Moreover many improvements are necessary for functioning of robot's location awareness. In this paper, we propose a more improved home robot system which uses resources of the robot efficiently as it divides the complicated operation of the robot among external digital device and adds new functions easily and recognizes the location of the robot by RFID.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.27 no.6
• /
• pp.1347-1359
• /
• 2017

SQLite database is a file-based DBMS(Database Management System) that provides transactions, and it is loaded on smartphone because it is appropriate for lightweight platform. AS the usage of smartphone increased, SQLite-related crimes can occur. In this paper, we proposed a new concealing method for SQLite db file and a detection method against it. As a result of concealing experiments, it is possible to intentionally conceal 70bytes in the DB file header and conceal original data by inserting artificial pages. But it can be detected by parsing 70bytes based on SQLite structure or using the number of record and index. After that, we proposed detection algorithm for concealed data.

• KIPS Transactions on Software and Data Engineering
• /
• v.8 no.1
• /
• pp.37-44
• /
• 2019

With the advance of digital IT technology, the performance of the printing and scanning devices is improved and their price becomes cheaper. As a result, the public can easily access these devices for crimes such as forgery of official and private documents. Therefore, if we can identify which printing device is used to print the documents, it would help to narrow the investigation and identify suspects. In this paper, we propose a deep learning model for printer identification. A convolutional neural network model based on local features which is widely used for identification in recent is presented. Then, another model including a step to calculate global features and hence improving the convergence speed and accuracy is presented. Using 8 printer models, the performance of the presented models was compared with previous feature-based identification methods. Experimental results show that the presented model using local feature and global feature achieved 97.23% and 99.98% accuracy respectively, which is much better than other previous methods in accuracy.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.19 no.2
• /
• pp.127-140
• /
• 2009

Recently, software piracy is one of the serious crimes for the digital materials. It makes economically devasting to the software industry and the market. In particular, it is a widespread phenomenon among university students in Korea and negative affects in measuring social and cultural level. Many studies have been focused on the users' intention of the software piracy for making anti-piracy policy. The purpose of this study is to investigate the factors affecting university students' software piracy intention. The survey includes responses from 271 university students in a school of business adminstration. The research model was estimated with multiple regression. The analysis showed results that user's characteristics, subjective norms, and perceived software quality were significantly related to intention of software piracy, but security policy was not. Perceived importance of intellectual property has negative impact on user's software piracy intention. Based on the findings, we suggest the implications for developing and implementing appropriate policies for anti-piracy.

• The Journal of Korean Institute of Information Technology
• /
• v.17 no.8
• /
• pp.11-19
• /
• 2019

Against advanced image-related crimes, a high level of digital forensic methods is required. However, feature-based methods are difficult to respond to new device features by utilizing human-designed features, and deep learning-based methods should improve accuracy. This paper proposes a deep learning model to identify camera models based on DenseNet, the recent technology in the deep learning model field. To extract camera sensor features, a HPF feature extraction filter was applied. For camera model identification, we modified the number of hierarchical iterations and eliminated the Bottleneck layer and compression processing used to reduce computation. The proposed model was analyzed using the Dresden database and achieved an accuracy of 99.65% for 14 camera models. We achieved higher accuracy than previous studies and overcome their disadvantages with low accuracy for the same manufacturer.

• Design & Manufacturing
• /
• v.16 no.1
• /
• pp.55-61
• /
• 2022

As meters become digital and smart, energy data such as electricity, gas, heat, and water can be accurately and efficiently measured with a smart meter, providing consumers with data on energy used, so that real-time demand response and energy management services can be utilized. Although it is developing from a simple metering system to a smart metering industry to create a high value-added industry fused with ICT, illegal counterfeiting of electronic meters is causing problems in intelligent crimes such as manipulation and hacking of SW. The meter not only allows forgery of the meter data through arbitrary manipulation of the SW, but also leaves a fatal error in the metering performance, so that the OIML requires the validation of the SW from the authorized institution. In order to solve this problem, a quantitative confirmation device was developed in order to eradicate the act of cheating the fuel oil quantity through encoder pulse operation and program modulation, etc. In order to prevent the act of deceiving the lubricator, a device capable of checking pulse forgery was developed, manufactured, and verified. In addition, the performance of the device was verified by conducting an experiment on the meter being used in the actual field. It is judged that the developed quantitative confirmation device can be applied to other flow meters other than lubricators, and in this case, accurate measurement can be induced.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.32 no.4
• /
• pp.723-736
• /
• 2022

Steganography is being used as a means of secret communication for crimes that threaten national security such as terrorism and espionage. With the development of computers, steganography technologies develop and criminals produce and use their own programs. However, the research for steganography is not active because detailed information on national security cases is not disclosed. The development of investigation technologies and the responses of criminal law are insufficient. Therefore, in this paper, the detection and decoding process was examined for steganography investigation, and the method was analyzed for 'the spy case of Pastor Kim', who was convicted by the Supreme Court. Multiple security devices were prepared using symmetric steganography using the pre-promised stego key. Furthermore, the three criminal legal issues: (1) the relevance issue, (2) the right to participate, and (3) the public trial issue a countermeasure were considered in national security cases. Through this paper, we hope that the investigative agency will develop analysis techniques for steganography.

• International Journal of Computer Science & Network Security
• /
• v.22 no.7
• /
• pp.315-319
• /
• 2022

Cloud computing has emerged to be the most effective headway for investigating crime especially cybercrime in this modern world. Even as we move towards an information technology-controlled world, it is important to note that when innovations are made, some negative implications also come with it, and an example of this is these criminal activities that involve technology, network devices, and networking that have emerged as a result of web improvements. These criminal activities are the ones that have been termed cybercrime. It is because of these increased criminal activities that organizations have come up with different strategies that they use to counter these crimes, and one of them is carrying out investigations using the cloud environment. A cloud environment has been defined as the use of web-based applications that are used for software installation and data stored in computers. This paper examines problems that are a result of cybercrime investigation in the cloud environment. Through analysis of the two components in play; cybercrime and cloud environment, we will be able to understand what are the problems that are encountered when carrying out investigations in cloud forensics. Through the use of secondary research, this paper found out that most problems are associated with technical and legal channels that are involved in carrying out these investigations. Investigator's mistakes when extracting pieces of evidence form the most crucial problems that take a lead when it comes to cybercrime investigation in the cloud environment. This paper not only flags out the challenges that are associated with cybercrime investigation in cloud environments but also offer recommendations and suggested solutions that can be used to counter the problems in question here. Through a proposed model to perform forensics investigations, this paper discusses new methodologies solutions, and developments for performing cybercrime investigations in the cloud environment.