My Skydrive is not protected

Why is my skydrive not verifying the email address I share my file with? I send a skydrive link to a colleague to access a file on my skydrive, but he log in with a different email address different from the one I use in the invite and skydrive doesn’t complain, granting him access. Is my skydrive under attack? How can I enforce skydrive to strictly enforce the email in the invite sent?
