Re: DarkStarlings.com XSS Vulnerability
While the site does not intensively scrub javascript that is input by the user,
XSS vulnerabilities are not a concern.
The worst case scenario (and really only important scenario) is that of a
malicious party using javascript to capture cookie information from a user of
the site and then using that information to falsely authenticate under the
user's account (or to put it garishly, using XSS to "hack" other member's
accounts).
Even though an XSS enthusiast of intermediate skill should have little trouble
extracting user cookie information on the site using cleverly disguised
redirects, the information obtained would be entirely useless.
Not only is the cookie password information hashed with multiple, complex,
salted algorithms, it is hashed with unique information (a unique salt that
depends upon some network information) that makes using the hashed password to
forge a cookie impossible. That is, User A and User B, connecting from
different locations but using the same username and password, will have
different password hashes. If User B tries to use User A's password hash,
authentication will fail.
Given that, I have elected not to pursue heavy scrubbing of javascript on my
site.
Why?
I could just as easily disabled the use of javascript site wide, but I wanted
to allow members of our community to be more free to use it for various
(benign) purposes. Instead of letting a few bad apples ruin the party for
everyone, I've carefully considered the consequences of attempted XSS exploits
using javascript on my site and have produced solutions to keep everyone's
experience on DarkStarlings as secure as possible.