攻防世界 REVERSE 新手区/game

攻防世界 REVERSE 新手区/game

下载得到附件
用IDA32位打开
先找下main函数

找到后按下f5进行反汇编

跟进main0 继续跳转

看到一个if语句，以及判断的条件推测这就是得到flag的条件

跟进sub_457AB4（）

继续跳转，看到提示，flag就在这里

根据算法写出脚本

#include <stdio.h>
#include <stdlib.h>


int main(void)
{
    int a[] = {18,64,98,5,2,4,6,3,6,48,49,65,32,12,48,65,31,78,62,32,49,32,
	   1,57,96,3,21,9,4,62,3,5,4,1,2,3,44,65,78,32,16,97,54,16,44,
	   52,32,64,89,45,32,65,15,34,18,16,0};
	int b[] = {123,32,18,98,119,108,65,41,124,80,125,38,124,111,74,49,
	   83,108,94,108,84,6,96,83,44,121,104,110,32,95,117,101,99,
	   123,127,119,96,48,107,71,92,29,81,107,90,85,64,12,43,76,86,
	   13,114,1,117,126,0};
    for (int i = 0; i < 56; ++i)
    {
        b[i] ^= a[i];
        b[i] ^= 0x13;
        printf("%c",b[i]);
    }
    return 0;
}

运行，得到flag