• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.6
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• pp.1267-1277
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• 2021

The phone number used for advertising messages and voices used as bait in the voice phishing crime access stage is being used to send out a large amount of illegal loan spam, so we want to quickly block it. In this paper, our system is designed to block the usage of the phone number by rapidly restricting the use of the voice spam phone number that conducts illegal loan spam and voice phishing, and at the same time sends continuous calls to the phone number to prevent smooth phone call connection. The proposed system is a representative collaboration model between an illegal spam reporting agency and an investigation agency. As a result of developing the system and applying it in practice, the number of reports of illegal loaned voice spam and text spam decreased by 1/3, respectively. We can prove the effectiveness of this system by confirming that.

• Journal of IKEEE
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• v.27 no.3
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• pp.213-219
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• 2023

According to statistics from the National Police Agency, smishing crimes using texts or messengers have increased dramatically since COVID-19. In addition, most of the cases of impersonation of public institutions reported to agency were related to vaccination and reward, and many methods were used to trick people into clicking on fake URLs (Uniform Resource Locators). When detecting them, URL-based detection methods cannot detect them properly if the information of the URL is hidden, and content-based detection methods are slow and use a lot of resources. In this paper, we propose a system for URL-based detection using transformer for regular URLs and content-based detection using XGBoost for shortened URLs through the process of determining shortened URLs using GRU(Gated Recurrent Units). The F1-Score of the proposed detection system was 94.86, and its average processing time was 5.4 seconds.

• Convergence Security Journal
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• v.23 no.1
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• pp.19-25
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• 2023

The current network environment provides a real-time interactive service from an initial one-way information prov ision service. Depending on the form of web-based information sharing, it is possible to provide various knowledge a nd services between users. However, in this web-based real-time information sharing environment, cases of damage by illegal attackers who exploit network vulnerabilities are increasing rapidly. In particular, for attackers who attempt a phishing attack, a link to the corresponding web page is induced after actively generating a forged web page to a user who needs a specific web page service. In this paper, we analyze whether users directly and actively forge a sp ecific site rather than a passive server-based detection method. For this purpose, it is possible to prevent leakage of important personal information of general users by detecting a disguised webpage of an attacker who induces illegal webpage access using traceback information

• Convergence Security Journal
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• v.23 no.5
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• pp.165-172
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• 2023

Nation-state social engineering attacks are steadily being carried out as they are highly effective attacks, primarily to gain an advantage over secret information, diplomatic negotiations or future policy changes. As The Ukraine-Russia war prolongs, the activities of global hacking organizations are steadily increasing, and large-scale cyberattack attempts against major infrastructure or global companies continue, so a countermeasure strategy is needed. To this end, we determined that the social engineering attack cycle excluding physical contact among various social engineering models is the most suitable model, and analyzed the preferred social engineering attack method by comparing it with geopolitical tactics through case analysis. AS a result China favors phishing attacks, which prefer quantity over quality, such as man-made tactics, Russia prefers covert and complex spear phishing reminiscent of espionage warfare, and North Korea uses geopolitical tactics such as spear phishing and watering holes for attacks on the US and South Korea Most of the other countries aimed to secure funds with ransomware. Accordingly, a Clean Pass policy for China, periodic compulsory education in Russia, and international sanctions against North Korea were presented as countermeasure strategies.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.5
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• pp.1021-1026
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• 2015

Increasing of damage by phishing, government and organization response more rapidly. So phishing use malware and vulnerability for attack. Recently attack that use patch analysis is increased when Microsoft announce patches. Cause of that, researcher for security on defense need technology of patch analysis. But most patch analysis are develop for Microsoft's product. Increasing of mobile environment, necessary of patch analysis on mobile is increased. But ordinary patch analysis can not use mobile environment that there is many file and small size. So we suggest this research that use code filtering instead of Control Flow Graph and Abstract Syntax Tree.

• Journal of Korean Society of Disaster and Security
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• v.5 no.1
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• pp.21-28
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• 2012

This study can be solved a means of authentication of electronic financial transactions. We suggest that smart devices can be useful to authenticate in electronic financial transactions regardless of time and place. Our new authentication method named Lock-Unlock authentication method with smart devices. This method will be expected to reduce many kind of accidents (theft, phishing, hacking, certificates and simple certified OTP, ATM withdrawals, ARS, etc.) by account locking in electronic financial transactions. And helpful to users can effectively protect electronic financial transactions and minimize the accident during get a electronic trading.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.267-270
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• 2013

Hacking damage is increasing year by year in the Internet payment service credit card applying the digital signature method of PKI-based first domestic, secure payment, was 180 million won in 2012. Revenues have soared for phishing that Smishing using smartphone after entering 2013. Hacking accident to the secure payment system using Smishing has occurred took over personal information and financial direct damage. In this paper, we analyzed for Smishing, to prevent the damage of secure payment using Smishing to study the hacking attack of secure payment. In addition, it would be studies to allow through the smartphone, online payment safer and more convenient.

• Journal of Convergence for Information Technology
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• v.11 no.6
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• pp.24-32
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• 2021

Recently, ransomware attacks have been infected through various channels such as e-mail, phishing, and device hacking, and the extent of the damage is increasing rapidly. However, existing known malware (static/dynamic) analysis engines are very difficult to detect/block against novel ransomware that has evolved like Advanced Persistent Threat (APT) attacks. This work proposes a method for modeling ransomware malicious behavior based on graph databases and detecting novel multi-complex malicious behavior for ransomware. Studies confirm that pattern detection of ransomware is possible in novel graph database environments that differ from existing relational databases. Furthermore, we prove that the associative analysis technique of graph theory is significantly efficient for ransomware analysis performance.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.52-60
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• 2024

APT (Advanced Persistent Threat) attack is a dangerous, targeted attack form with clear targets. APT attack campaigns have huge consequences. Therefore, the problem of researching and developing the APT attack detection solution is very urgent and necessary nowadays. On the other hand, no matter how advanced the APT attack, it has clear processes and lifecycles. Taking advantage of this point, security experts recommend that could develop APT attack detection solutions for each of their life cycles and processes. In APT attacks, hackers often use phishing techniques to perform attacks and steal data. If this attack and phishing phase is detected, the entire APT attack campaign will be crash. Therefore, it is necessary to research and deploy technology and solutions that could detect early the APT attack when it is in the stages of attacking and stealing data. This paper proposes an APT attack detection framework based on the Network traffic analysis technique using open-source tools and deep learning models. This research focuses on analyzing Network traffic into different components, then finds ways to extract abnormal behaviors on those components, and finally uses deep learning algorithms to classify Network traffic based on the extracted abnormal behaviors. The abnormal behavior analysis process is presented in detail in section III.A of the paper. The APT attack detection method based on Network traffic is presented in section III.B of this paper. Finally, the experimental process of the proposal is performed in section IV of the paper.

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.1-22
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• 2015

Due to recent growth in IT industry along with the expansion of smartphone, we came to connect to the Internet wherever and whenever we are. However, this causes negative side effects, though. One of them is a rapid increase of the financial crimes such as the Phishing and the SMishing. There have been many on-going researches about crimes such as Phishing and SMishing to protect users. However, the study about sharing knowledge on SNS to prevent such a crime can be hardly found. Based on social identity theory, we conduct the research about factors on SNS users' intention to share the information security knowledge on SNS. As a result, we found that knowledge provision self-efficacy has a significant impact on self-expression. In addition, it also found out self-expression, awareness about information security and the sense of belonging have a significant impact respectively on the intention to share the information security knowledge on SNS. On the other hand, the altruism didn't have a significant impact to the intention to share information security knowledge on SNS. With this research as a starting point, it seems necessary to expand its range to all types of online community in the future for the generalization of the hypotheses.