1. Login level00(Check login status using whoami command)
2. Insert command : find / -perm -4000 -user flag00 -exec ls -al 1> ~/00result.txt 2> /dev/null {} \;
A. find : Command to search for files or folders
B. -perm -4000 : The authority includes at least 4000
C. -user flag00 : Owner name flag00
D. -exec ls -al 1> ~/00result.txt 2> /dev/null {} \; : It records list of search results in ~/00esult.text. And It throws away error messages in the trash
3. In the 00result.txt, There is suspicious two file records
4. When you execute the file "/bin/.../flag00" and "/rofs/bin/.../flag00",
5. When you enter a command getflag, Clear level 00!