Security flaw: hacker can gain access to username

Hello, I am using Catch Everest for one of my sites and think it is very good. Unfortunately, if I click on the author name of a post then it takes me to a list of all the posts by that author. Although I use a nickname on the site, to hide my username from hackers, the theme helpfully shows the real username in the URL: http://theeschercycle.com/author/bodmin/ I believe this is a security flaw. Is it possible please to update and reissue the theme (using the nickname in the URL, or "author-5" as you do on one of your other themes). Thank you