UAF (use after free) 예제코드

세미나용으로 만든 UAF 예제코드 

#include <iostream>

#include <stdlib.h>

#include <string.h>

#include <stdio.h>

using namespace std;

class B

{

public:

char *v1 = NULL;

virtual void foo(int a)

{

cout << "B Foo Call" << a << endl;

}

};

class D : public B

{

public:

char *buff;

void foo(int a)

{

cout << "D Foo Call " << a << endl;

}

};

class E

{

public:

char buff[24]="";

void test(int a){

cout << "E->TEST "<<endl;

}

void copy(char *v2){

memcpy(buff,v2,20);

}

};

int foo3(){

cout << "This is UNUSING FOO " <<endl;

return 0;

}

int (*funcAddr)() = foo3;

int main(int argc, char *argv[]){

char * test;

B *d,*b;

E *e;

printf("-------------------------------\n");

printf("[PRINT] UNUSING FOO function addr %x \n",&funcAddr);

printf("-------------------------------\n");

d = new D;

delete d;

e = new E;

e->copy(argv[1]);

printf("d->foo(9) call \n");

d->foo(9);

return 0;

}