1.下载附件，exeinfo查壳，无壳
2.32位IDA分析，进入主函数内
int __cdecl main(int argc, const char **argv, const char **envp)
{int result; // eaxint v4; // [esp+5Ch] [ebp-70h]char *v5; // [esp+60h] [ebp-6Ch]char v6[27]; // [esp+6Ch] [ebp-60h] BYREFchar v7; // [esp+87h] [ebp-45h]char *v8; // [esp+88h] [ebp-44h]char *v9; // [esp+8Ch] [ebp-40h]char *v10; // [esp+90h] [ebp-3Ch]char v11[12]; // [esp+98h] [ebp-34h] BYREFchar v12[24]; // [esp+A4h] [ebp-28h] BYREFint v13; // [esp+C8h] [ebp-4h]sub_402930();v13 = 0;sub_401530((int)&unk_4DDAF8, "please input flag");sub_4039B0(sub_402310);sub_401500(&dword_4DDA80, v12);if ( sub_405DE0(v12) == 24 ){sub_402A20(v11);LOBYTE(v13) = 1;sub_402570(v11);v10 = v12;v9 = (char *)sub_405270(v12);v8 = (char *)sub_4052B0(v12);while ( v9 != v8 ){v7 = *v9;sub_403B70(v7);++v9;}qmemcpy(v6, "rxusoCqxw{yqK`{KZqag{r`i", 24);sub_402590(v6);v5 = (char *)sub_405290(v11);v4 = sub_4052E0(v11);while ( v5 != (char *)v4 ){if ( !(unsigned __int8)sub_403BB0(*v5) ){sub_401530((int)&unk_4DDAF8, "error");sub_4039B0(sub_402310);LOBYTE(v13) = 0;sub_4034E0(v11);v13 = -1;sub_403450(v12);return 0;}++v5;}sub_401530((int)&unk_4DDAF8, "good job");sub_4039B0(sub_402310);LOBYTE(v13) = 0;sub_4034E0(v11);v13 = -1;sub_403450(v12);result = 0;}else{sub_401530((int)&unk_4DDAF8, "not enought");sub_4039B0(sub_402310);v13 = -1;sub_403450(v12);result = 0;}return result;
}int __thiscall sub_403B70(void *this, char a2)
{char v3[65]; // [esp+Fh] [ebp-45h] BYREFvoid *v4; // [esp+50h] [ebp-4h]v4 = this;v3[0] = a2 ^ 0x14;//进行异或sub_406170(v3);return ++dword_4DD8F8;
}
3.最终脚本：
s ='rxusoCqxw{yqK`{KZqag{r`i'
for i in range(len(s)):print (chr(ord(s[i])^0x14),end = '')#include<stdio.h>
#include<stdlib.h>
#include<string.h> int main()
{char a[]="rxusoCqxw{yqK`{KZqag{r`i";int i;for(i=0;i<24;i++){a[i]=a[i]^20;//20来源：在IDA中快捷键H将0x14转化为十进制20printf("%c",a[i]);}return 0;
} 
flag{Welcome_to_Neusoft}
