Accessing Cookies of Other Domains using JavaScript/Java

Question

I am developing a Analytics Software and there is a need to fetch or read User Behaviour from competitor websites. I am thinking that accessing the information from cookies of the competitor site would be a better option. Is there any alternative to this. Also, How to access cookies from all domains using either JavaScript or Java.

Answer 1

If this would have been possible the e-commerce world would have been different. It was possible in early browsers but in modern browsers you cannot access cookies from other domains .

Answer 2

And if this is possible it is a security risk too, because typically information regarding sessions on a website will be stored in a cookie. If you are able to read cookies on other domains that is a security breach.