Postbook - FLAG5 0x00 Cookie user cookie id: "c81e728d9d4c2f636f067f89cc14862c" Check at cmd5.com. It is just md5 value of 2. 0x01 Admin Cookie md5(1) id: "c4ca4238a0b923820dcc509a6f75849b" 0x02 FLAG Successfully login as admin.