旧日絮语（图片高度修改+图片隐写+docx隐写+逆向）

修改png的高


binwalk分离

使用key解压缩docx


得到压缩包，需密码
key:shenglingshidai

ida逆向发现key函数

#include <stdio.h>
#include <string.h>
int main()
{
  int flag[50]; // [esp+10h] [ebp-268h]
  int b[50]; // [esp+D8h] [ebp-1A0h] BYREF
  int a[50]; // [esp+1A0h] [ebp-D8h] BYREF
  int j; // [esp+268h] [ebp-10h]
  int i; // [esp+26Ch] [ebp-Ch]

  memset(a, 0, sizeof(a));
  a[0] = 1;
  a[1] = 6;
  a[2] = 8;
  a[3] = 9;
  a[4] = 8;
  a[5] = 6;
  a[6] = 2;
  a[7] = 6;
  a[8] = 7;
  a[9] = 7;
  memset(b, 0, sizeof(b));
  b[0] = 2;
  b[1] = 9;
  b[2] = 5;
  b[3] = 6;
  b[4] = 7;
  b[5] = 5;
  b[6] = 7;
  b[7] = 6;
  b[8] = 6;
  b[9] = 4;
  j = 0;
  for ( i = 0; i <= 31; ++i )
  {
    if ( j > 8 )
      j = 0;
    flag[i] = b[j] + a[j];
  }
  for ( i = 0; i <= 31; ++i )
    flag[i] += a[i];
  printf("flag{");
  for ( i = 0; i <= 17; ++i )
    printf("%d", flag[i]);
  printf("}");
  return 0;
}