Gregory Maxwell wrote:
Please no scare mongering. Wikimedia sites are not
vulnerable to this.
I reproduced the vulnerability the day it hit Slashdot and determined
that it posed no special risk to us.
[...]
The reason that Wikimedia sites are not vulnerable is
that wikimedia
sites confine all user uploaded files to
upload.wikimedia.org which
holds nothing but these files. XSS attacks via uploaded files (which
is what this effectively is, though it's using Java) end up confined
by browser behaviour to only access that particular domain (or IP, in
the case of Java). Since there is nothing worth targeting on that IP
(no login, no cookies, no forms, etc) it couldn't do much.
All the same, I'd rather not have such files on our servers. I'm glad
someone finally reported this, and it would have been nice if you filed a
bug at the time.
Even if Wikimedia is not vulnerable, many other MediaWiki installations
will be.
-- Tim Starling