Cryptography BLURY Description : Mr. Charlie Ben Conor's security algorithms have been repeatedly urged by the management team to include as much randomization as possible. We believe he lacks understanding of conventional uses of symmetric cyphers, but he has always denied it owing to financial constraints. Can you demonstrate the potential ... Read More

Forensics Attaaaaack1 Description : One of our employees at the company complained about suspicious behavior on the machine, our IR team took a memory dump from the machine and we need to investigate it. Q1. What is the best profile for the the machine? 회사 직원 중 한 명이 시스템의 의심스러운 동작에 대해 불평했고, IR 팀이 시스템에서 메모리 덤프를 가져와 조사해야 했습니다. Q1. 기계에 가장 적합한 프... Read More

Reversing back-to-basics Description : Try to solve it with your eyes closed Attached file : [ReverseEngineeringChallenge.java] 문제 풀이 뭐라는지 모르겠다… 일단 준 파일을 실행해보았다. 근데, Java가 설치가 안되있는건지 실행되지 않았다. ida나 ghydra로도 열리지 않아, 일단 hxd로 열어보았다. password 뭐시기가 적혀있다. 실행 되는 프로그램인가…? 노트북 구석진 곳에 있던 java 디컴파일 프로그램을 통해 열어보았다. password가 하드코딩되어 한... Read More

Reversing obfuscJStor Description : Obfuscated JavaScript?? Really?? Attached file : [obfuscJStor.js] function _0x12de(){var _0x6ab222=['\x2e\x69\x6f','\x75\x73\x63\x61\x74','\x37\x32\x4f\x4f\x6e\x7a\x73\x4d','\x61\x5f\x74\x6f\x6f','\x6c\x6f\x67','\x62\x79\x75\x63\x74','\x32\x30\x35\x38\x31\x31\x31\x56\x73\x4a\x6d\x4e\x74','\x64\x61\x79\x73\x... Read More