revmem

revmem

The binary generates a flag that is compared with the user input using strcmp.

Easy way

ltrace ./revmem whatever

Will print the strcmp arguments, so we can just copy the flag.

"Hard" way

Very similar to the last part of keycheck_baby.

This solution is in flag_cracker.c.

Alternative solution

Using Ghidra we can see that the function strncmp in the main is called at the offset 0x22d within the code segment. Using gdb we can set a breakpoint at the address 0x55555555522d and see the parameters passed to the function.