If you open the file on ghidra, and analyze to decompile you will get the following code in the main function:
{
int iVar1;
size_t sVar2;
undefined8 uVar3;
char local_98 [8];
char acStack_90 [8];
char acStack_88 [8];
char acStack_80 [8];
char acStack_78 [108];
int local_c;
puts("What was the flag again?");
fgets(local_98,0x80,stdin);
strip_newline(local_98);
sVar2 = strlen(local_98);
if (sVar2 == 0x28) {
local_c = 0;
iVar1 = strncmp(acStack_90,"t_what_f",8);
local_c = local_c + (uint)(iVar1 == 0);
iVar1 = strncmp(acStack_78,"t_means}",8);
local_c = local_c + (uint)(iVar1 == 0);
iVar1 = strncmp(acStack_80,"nd_forge",8);
local_c = local_c + (uint)(iVar1 == 0);
iVar1 = strncmp(local_98,"lactf{no",8);
local_c = local_c + (uint)(iVar1 == 0);
iVar1 = strncmp(acStack_88,"orgive_a",8);
local_c = local_c + (uint)(iVar1 == 0);
switch(local_c) {
case 0:
puts("No, that definitely isn\'t it.");
uVar3 = 1;
break;
case 1:
puts("I\'m pretty sure that isn\'t it.");
uVar3 = 1;
break;
case 2:
puts("I don\'t think that\'s it...");
uVar3 = 1;
break;
case 3:
puts("I think it\'s something like that but not quite...");
uVar3 = 1;
break;
case 4:
puts("There\'s something so slightly off but I can\'t quite put my finger on it...");
uVar3 = 1;
break;
case 5:
puts("Yes! That\'s it! That\'s the flag! I remember now!");
uVar3 = 0;
break;
default:
uVar3 = 0;
}
}
else {
puts("No, I definitely remember it being a different length...");
uVar3 = 1;
}
return uVar3;
}
You can see the flag, but it is defragmented, so if you put it thogeter, you will get the flag, you just need to put based on the number of the variable,so the first one is local_98, because it starts with lactf{no, so if you follow the stack from bigger to smaller you will get the follow sequence:
local_98, acStack_90, acStack_88, acStack_80, acStack_78 which translate to lactf{not_what_forgive_and_forget_means} which is the flag!
