Because Git is a distributed version control system, GitHub must use the commit email address to assign attribution. When you push a repository to GitHub.com it may contain one or more commits, some of which you may not have authored. For example, imagine a scenario where you collaborated with a number of people on a git repository before you made your first push of that repository to GitHub.com. This push would contain a number of commits from several authors. It would be incorrect to assign all of the commits to the person doing the push, so we use the commit log email addresses to assign attribution on GitHub.com. Each subsequent push to GitHub uses this same logic to assign attribution of commit authors.
It’s important to note that impersonating another GitHub user in this fashion doesn’t grant you access to any of their repositories or give you any privileges you didn’t already have. However, GitHub does consider impersonation an account abuse issue that we take very seriously. If someone is wrongfully impersonating you, please let us know and we will investigate the matter and deal with it as quickly as we can. In addition, if you are still concerned about this, you and your team can choose to use Git’s built in options to sign commits with a GPG key (check out the
git commit -S command).
bounty.github.com, as well as several other GitHub owned sites, are created using a static site generator and hosted on GitHub Pages. These applications do not contain any sensitive user information or authenticated sessions. As a result, they are not at risk of a clickjacking attack.