• The KIPS Transactions:PartA
• /
• v.8A no.4
• /
• pp.385-390
• /
• 2001

In this paper, we describe a blocking method of buffer overflow attack for secure operating system. Our team developed secure operating system using MAC and ACL access control added on Linux kernel. We describe secure operating system (SecuROS) and standardized Secure utility and library. A working prototype able to detect and block buffer overflow attack is available.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.17 no.1
• /
• pp.67-80
• /
• 2007

Nateon Messenger, which has the most number of users in Korea, supports many services such as E-mail, note, Cyworld, SMS, etc. In this paper, we will analyse the authentication traffic which is transmitted and received by the Nateon Messenger. Through performing the replay attack with the authentication information, we will show that an attacker can be authenticated illegally. Furthermore, we will show that other domestic messengers have similar security problems.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
• /
• 2001.11a
• /
• pp.277-280
• /
• 2001

기존 시스템 취약성 공격이나 스캔 공격도구들로부터 최근에는 방화벽이나 기타 보안 시스템을 우회하기 위한 보다 진보된 공격 도구들이 나타났다. 이중 가장 심각한 것이 커널 백도어인데 이는 기존의 사용자 레벨에서가 아닌 커널레벨에서 수행되는 특징을 가진다. 이러한 커널 백도어는 기존의 탐지기술로는 탐지가 불가능하며 현재 피해사례도 정확히 파악되지 않아 그 피해는 더욱 크다 하겠다. 이에 본 논문에서는 현재 배포되어 있는 커널 백도어를 분석하고 기존의 커널 백도어 탐지 기술과 이의 문제점을 해결하는 새로운 커널 백도어 탐지 모델과 구현 방안을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2017.11a
• /
• pp.239-242
• /
• 2017

스마트폰에 저장되는 개인정보가 늘어나면서 이를 보호하기 위한 여러가지 인증기법이 제안되었다. 이중 안드로이드 OS에 탑재된 패턴락은 가장 많이 사용되는 인증기법 중 하나이지만 Smudge 공격과 Shoulder surfing 공격에 취약하다고 알려져 있다. LG 전자는 패턴락에 비해 보안성, 편리성이 뛰어난 노크코드라는 기법을 고안하였다. 노크코드는 꺼진 화면에 사용자가 정한 영역을 순서대로 '터치'함으로써 인증을 완료한다. 본 논문에서는 '터치'만을 사용하는 기존 노크코드 기법에 '슬라이드'를 입력으로 추가할 수 있도록 변형시킨 기법 두 가지를 제안하였다. 분석 결과, 기존 기법에 비해 패스워드의 길이가 n(6~8)으로 같을 경우 패스워드의 개수가 $4^n$배까지 증가했음을 정량적으로 보였고 슬라이드 입력을 이용해 Smudge를 직접적으로 제거함으로써 Smudge 공격에 대한 저항력을 높일 수 있음을 보였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.42 no.1
• /
• pp.233-240
• /
• 2017

Due to a recent rise in use of a wireless keyboard and mouse, attacks which take user's input information or control user's computer remotely exploiting the physical vulnerability in the wireless communication have been reported. Especially, MouseJack, announced by Bastille Network, attacks 2.4 GHz wireless keyboards and mice through exploiting vulnerability of each manufacturer's receiver. Unlike other attacks that have been revealed, this allows to attack AES wireless keyboards. Nonetheless, there is only a brief overview of the attack but no detailed information on this attacking method. Therefore, in this paper we will analyze the Microsoft 2.4 GHz wireless mouse packet and propose a way to set the packet configuration for HID packet injection simulating a wireless mouse. We also develop a system with 2.4 GHz AES wireless keyboard HID packet injection using the proposed packet and demonstrate via experiment that HID packet injection is possible through the system we built.

• Convergence Security Journal
• /
• v.12 no.1
• /
• pp.17-25
• /
• 2012

SQL Injection techniques disclosed web hacking years passed, but these are classified the most dangerous attac ks. Recent web programming data for efficient storage and retrieval using a DBMS is essential. Mainly PHP, JSP, A SP, and scripting language used to interact with the DBMS. In this web environments application does not validate the client's invalid entry may cause abnormal SQL query. These unusual queries to bypass user authentication or da ta that is stored in the database can be exposed. SQL Injection vulnerability environment, an attacker can pass the web-based authentication using username and password and data stored in the database. Measures against SQL Inj ection on has been announced as a number of methods. But if you rely on any one method of many security hole ca n occur. The proposal of four levels leverage is composed with the source code, operational phases, database, server management side and the user input validation. This is a way to apply the measures in terms of why the accident preventive steps for creating a phased step-by-step response nodel, through the process of management measures, if applied, there is the possibility of SQL Injection attacks can be.

• Journal of the Korea Convergence Society
• /
• v.2 no.4
• /
• pp.9-14
• /
• 2011

Phishing is an attack to theft an user's identity by masquerading the user or the device. The number of phishing victims are sharply increased due to wide spread use of smart phones and messenger programs. Smart phones can operate various wi-fi based apps besides typical voice call and SMS functions. Generally, the messenger program such as Kakao Talk or Nate On is consisted of client and server functions. Thus, the authentication between the client and the server is essential to communicate securely. In this paper, we propose the messenger authentication protocol safe against smart phone phishing. To protect communications among clients, the proposed method provides message encryption and authentication functions.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.1 no.1
• /
• pp.67-74
• /
• 2008

As wireless network market is increasing rapidly, the biggest issue is to transfer safe data and to authenticate users. This paper proposes ECbA(Elliptic Curve based Authentication) which consists of the mutual authentication mechanism that users can ascertain the identity of an authentication server and the user authentication mechanism that an authentication server can make sure users' identity, by using Elliptic Curve algorithms. The proposed ECbA system diminishes the message quantity and the execution time by using the small elliptic curve algorithm with the small key length in authentication. In addition, as this paper reduces the authentication steps of existing EAP_TLS into 6 authentication steps, the communication cost and mutual authentication time can be saved. As this paper distributes new keys, whenever authenticating users by using key exchange mechanism, it provides safe encryption communication and prevents DoS attack by controlling the users authentication request by authentication server.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.11
• /
• pp.2109-2114
• /
• 2017

Personal Identification Number (PIN) is the most common user-authentication method for the access control of private and commercial applications. The users need to enter PIN information to the applications whenever the users get access to the private services. However, the process imposes a burden on the users and is vulnerable to the potential shoulder-surfing attacks. In order to resolve both problems, we present a continuous authentication method for both smartphone and smartwatch, namely, synchronized authentication. First we analyze the previous smartwatch based authentication and point-out some shortcomings. In the proposed method, we verify the validity of user by analyzing the combined acceleration data of both smartphone and smartwatch. If the monitored sensor data shows the high correlations between them, the user is successfully authenticated. For the authentication test, we used the Samsung Galaxy Note5 and Sony Smartwatch2.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.9
• /
• pp.81-88
• /
• 2021

In this paper, we analyze the possibility of deregistration attack in 5G SNPN (Standalone Non-Public Network) based on 3GPP standard document. In the deregistraion attack, the attacker pretends to be a UE that is normally registered with AMF (Access and Mobility Management Function) and attempts to establish a spoofed RRC (Radio Resource Control) connection, causing AMF to deregister the existing UE. The existing deregistration attack attempts a spoofed RRC connection to the AMF in which the UE is registered. In addition, this paper analyzes whether deregistration attack is possible even when an attacker attempts to establish a spoofed RRC connection to a new AMF that is different from the registered AMF. When the 5G mobile communication network system is implemented by faithfully complying with the 3GPP standard, it is determined that a deregistration attack of a UE is impossible.