Why is this code working

Looking at this piece of code:

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

typedef struct _point{
  int x;
  int y;
} point;

int main (void)
{

 point *ptr;
 point obj;

 ptr = (point *)malloc(sizeof(char));
 obj.x = 500;
 obj.y = 5000;
 memcpy((void *)ptr, (void *)&obj, sizeof(point));
 printf("point.x = %d, point.y = %d\n", ptr->x, ptr->y);
 return 0;
}

Why is it running correctly when I run it. Shouldn't I get a segfault given I incorrectly do malloc() on sizeof(char) instead of sizeof(point)?