• The KIPS Transactions:PartC
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• v.18C no.6
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• pp.369-378
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• 2011

To ensure data confidentiality and fine-grained access control in business environment, system model using KP-ABE(Key Policy-Attribute Based Encryption) and PRE(Proxy Re-Encryption) has been proposed recently. However, in previous study, data confidentiality has been effected by decryption right concentrated on cloud server. Also, Yu's work does not consider a access privilege management, so existing work become dangerous to collusion attack between malicious user and cloud server. To resolve this problem, we propose secure system model against collusion attack through dividing data file into header which is sent to privilege manager group and body which is sent to cloud server. And we construct the model of access privilege management using AONT based XOR threshold Secret Sharing, In addition, our scheme enable to grant weight for access privilege using XOR Share. In chapter 4, we differentiate existing scheme and proposed scheme.

• The KIPS Transactions:PartC
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• v.10C no.6
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• pp.739-746
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• 2003

In real life, we frequently use th proxy signatrue by delegating one's own privileges. It is necessary to distribute the data related to privilege delegation securely in order to use such a proxy signature in the Internet. However, inorder to use the secure proxy signature, we need to have some mechanism to prevent a proxy signer from misuse of privileges by applying proxy certificate and a privilege delegation mechanism to manage information with related to privilege delegarion. In addition, we have implemented the prototype to demonstrate the possible proxy signature service using proxy certificate.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.6
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• pp.1023-1030
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• 2020

Wearable devices, such as a smart watch and a wrist band, store owner's private information in the devices so that security in a high level is required. Applications developed by third parties in Tizen request for an access to designated services through the desktop bus (D-Bus). The D-Bus verifies application's privileges to grant the request for an access. We developed a fuzzing tool, so-called DAN (the D-bus ANalyzer), to detect errors in implementations for privilege verifications and access controls within Tizen's system services. The DAN has found a number of vulnerable services which granted accesses to unauthorized applications. We built a proof-of-concept application based on those findings to demonstrate a bypass in the privilege examination.

• Convergence Security Journal
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• v.8 no.3
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• pp.25-31
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• 2008

SELinux, security operating system, is the security system which implements mandatory access control using linux security module on the traditional linux kernel supporting discretionary access control. But intrusion detection and logging are lacked when system intrusions are happened. This study proposes a SELinux security kernel which performs detection of access violation and privilege restriction using dynamic access control. It detects the intrusion using security check when the abnormal access of system is happened, and dynamically changes the system privilege for the intruder through privilege restriction. Finally we prevent reintrusion and explain the result of experiment.

• Journal of Korea Society of Digital Industry and Information Management
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• v.15 no.3
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• pp.101-109
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• 2019

In addition to enabling access, database accounts play a protective role by defending the database from external attacks. However, because only a single account is used in the database, the account becomes the subject of vulnerability attacks. This common practice is due to the lack of database support, large numbers of users, and row-based database permissions. Therefore if the logic of the application is wrong or vulnerable, there is a risk of exposing the entire database. In this paper, we propose a Least-Privilege Account Separation Model (LPASM) that serves as an information guardian to protect the database from attacks. We separate database accounts depending on the role of application services. This model can protect the database from malicious attacks and prevent damage caused by privilege escalation by an attacker. We classify the account control policies into four categories and propose detailed roles and operating plans for each account.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.6A
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• pp.75-83
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• 2008

In this paper, we design a user authentication method between domains when mobile node moves in AAA server based MIPv6 environment. Several papers proposed the user authentication method executing at AAA server in home domain via AAA server in visiting domain. In this paper we proposed the user authentication method using privilege certificates between domains.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2002.11a
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• pp.548-550
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• 2002

본 논문은 PKC(Public Key Certificate)를 이용하여 Privilege Management를 제공하는 모델에 대해 다룬다. 권한관리는 PKC와 AC(Attribute Certificate)를 이용한 PMI가 제시되고 있으나, PMI를 구축하기 위한 비용이 들게 된다. 본 논문에서는 현재 구성되고 있는 PMI 모델과 본 논문에서 제시한 PSL(Privilege Status List)를 이용한 권한 관리모델을 비교, 분석한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.637-639
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• 2003

컴퓨터 시스템의 발달로 인해 여러 사용자가 여러 자원을 동시에 사용할 수 있는 환경으로 발전하면서 기존의 사용자 기반의 접근제어가 아닌 역할을 중심으로 하는 접근제어 모델이 제안되었다. 이러한 역할기반 접근제어 기법을 위한 참고 모델로서 역할 그래프 모델이 소개되었지만, 엄격한 충돌 처리 방식 때문에 실제 응용시스템에 적용하는 것은 한계가 있었다. 본 논문에서는 이러한 한계를 극복하기 위해서 충돌되는 권한을 세분화하고 이를 이용하여 좀 더 유연한 권한 삽입 연산을 할 수 있도록 하였다. 이러한 유동적 권한 삽입 방식을 통해 역할 그래프 모델을 좀 더 다양하게 적용한 수 있을 것이다.

• The Korean Society of Law and Medicine
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• v.12 no.2
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• pp.295-316
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• 2011

If the medical staff privileges, which mean the eligibility to practice at open hospitals, are excluded in the United States, antitrust claims based on the violation of the Sherman Act have been raised a lot. The proliferation of these lawsuits in the United States, which are characterized as antitrust lawsuits, can be understandable situation. The reason is because doctors who don't belong to specific hospitals are seriously damaged, if the medical staff privileges are excluded and doctors cannot use facilities of open hospitals. In order to decide to allow the privileges of certain doctors, hospitals have to rely on peer review to maintain high quality of medical services, and it is not easy to find alternative of peer review in the professional areas like healthcare. However, there are possibilities that members of the peer review can abuse power to unfairly exclude privileges of potential competitors. In this sense, it is asserted in the U.S. antitrust lawsuits that the restraint of medical staff privilege can be the illegal restraint of trade in violation of section 1 of Sherman Act and can be monopolization or an attempt to monopoly by hospitals in violation of section 2 of Sherman Act. As Korea adopted open hospital system quite recently, there is still no case related with the exclusion of medical staff privileges. However, medical staff privilege system of Korea is not different from that of the United States in principle. Thus, the U.S. jurisprudence on the exclusion of medical staff privileges can be referred in the interpretation of "practice that interferes with or restricts the activities or contents of the business" based on Article 19.1.9 of Monopoly Regulation and Fair Trade Law of Korea.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.3
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• pp.601-613
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• 2012

It is required to design and implement secure web applications to provide safe web services. For this reason, there are several scoring frameworks to measure vulnerabilities in web applications. However, these frameworks do not classify according to seriousness of vulnerability because these frameworks simply accumulate score of individual factors in a vulnerability. We rate and score vulnerabilities according to probability of privilege acquisition so that we can prioritize vulnerabilities found in web applications. Also, our proposed framework provides a method to score all web applications provided by an organization so that which web applications is the worst secure and should be treated first. Our scoring framework is applied to the data which lists vulnerabilities in web applications found by a web scanner based on crawling, and we show the importance of categorizing vulnerabilities according to privilege acquisition.