Yosuke Chubachi is a security engineer at FFRI, Inc. since this spring. He studied at the graduate school of information system engineering, University of Tsukuba. His research interests are in operating system and virtual machine monitoring. Particular interests include access control and intrusion prevention systems. He is a Security Camp lecturer (national information security human resource development program ) since 2011 and member of executive committee of SECCON (SECurity CONtest, the largest CTF organizer in Japan) since 2012.