The “NateOn” messenger is the most popular messenger in Korea (It has 17,160,000 users in Korea). In this paper, we will analyze
the security of authentication mechanism of the NateOn. We will show that the “NateOn Ver 3.5.15.0(600)” is very vulnerable
to the replay attack and the dictionary attack. Furthermore, we will show that other messengers such as “BuddyBuddy Ver 5.8”
(It has 5,980,000 users in Korea), “Daum Touch Ver 5.06101300” (It has 2,384,000 users in Korea), etc. have the similar security
problems.
This research was supported by the MIC (Ministry of Information and Communication), Korea, under the ITRC (Information Technology
Research Center) support program supervised by the IITA (Institute of Information Technology Advancement). (IITA-2006-C1090-0603-0028).