[Writeup][Break In CTF 2017][Reverse] Simple Secret - Part 1

Download here

Hint:

“Mandy and Aalekh are good friends. Once Mandy thought of giving Aalekh a challenge where Aalekh has to extract the secret key used by Mandy in his C program. The executable generated by Mandy is given below. Can you help Aalekh in finding the secret key hidden by Mandy?”

Tag: #ReverseEngineering
After download we have a file a.out
You can check file type and open it using ida64
That result:

a.out; ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, not stripped

And C code in ida64

int __cdecl main(int argc, const char **argv, const char **envp)
{
  int result; // eax@4
  __int64 v4; // rdx@4
  char v5; // [sp+10h] [bp-2720h]@1
  __int64 v6; // [sp+2728h] [bp-8h]@1

  v6 = *MK_FP(__FS__, 40LL);
  scanf("%s", &v5, envp, argv);
  if ( &v5 == "the_flag_is_bond_007" )
    puts("Gotcha");
  else
    puts("Better luck next time");
  result = 0;
  v4 = *MK_FP(__FS__, 40LL) ^ v6;
  return result;
}

But easy way is open it using notepad and search flag
Flag:

bond_007

^ ^ That all!!

[Writeup][Break In CTF 2017] Hello world

Question here

Question is:

“Can you find the flag?”

And tag is #Web

So let see html source of web. Very easy! You can see:

Can you find the flag?<!--the_flag_is_ForeverYoung --></p>

^^ Easy flag is:

ForeverYoung

That all!!!