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Beta Version of Nevercookie Released
wiredmikey writes "Anonymizer has released a beta version of Nevercookie, the recently announced Firefox plugin designed to protect against the Evercookie, a JavaScript API built and made available to prove that the more you store and the more places you store it, the harder it is for users to control a Web site's ability to uniquely identify their computer. Evercookie is a more persistent form of cookie that enables the storage of cookie data in a number of different locations, such as Flash cookies and various locations of HTML5 storage. This allows websites to track user behavior even when users have enabled private browsing. Because an Evercookie stores data in locations outside of where standard cookies are stored, an Evercookie can rebuild itself unless users go through a number of steps to completely clear and reset their local storage."
I could say what I always say about Privoxy. But it never sinks in, so instead here's an amusing link
Your system's clock skew fingerprint will give you away, with a tiny bit of Javascript. Who needs cookies, when your computer has intrinsic characteristics / artifacts from manufacturing that uniquely identify it?
I have been using, for many years, a script that was originally intended to defeat Firefox's attempt to always run all browser windows under the same process. The method used is to create a fake home directory and populate it with some data that was derived from a "first run" of Firefox. The script applies a few tweaks to make the paths match the dynamically generated fake home directory. Firefox believes it is the home directory. It doesn't go so far to double check this in /etc/passwd or such ... why would Firefox want to be that pedantic. If I had to, I could go a step further and defeat even that.
The intent of that script was to keep Firefox from getting overly bloated by allowing me to full quit (exit the process) for each site visited, without killing the windows of other sites I am still currently visiting. In some cases, some sites have triggered bugs, or caused lockups. I can kill the browser for that site (if it didn't crash on its own), still keeping the windows of other sites. It might seem counter-intuitive to many, but this does work to keep the bloat level down. At least it does so with my style of browsing (I keep a number of individual sites up in a browser sometimes for weeks).
One effect I did notice early on is that tracking was not happening if I quit a browser for one site and later started a new one to return. All the old cookies disappeared when the reaper component of the script cleaned up the leftover fake home directories. Cross site tracking wasn't happening as long as I started a new browser for each site, which I usually did, except when following links (in which case, they can get a referrer URL which I have not yet bothered to suppress). Referrers are sometimes useful (like to get a special pass through a paywall when coming from a partner site).
If it turns out that Firefox is so leaky that cookies can be placed outside of the context of the fake home directory, then I'll just have to raise the stakes and use a chroot directory (definitely not secure once arbitrary code can be run), or go even further and use either BSD Jails or Linux Containers (LXC, based on kernel cgroups). That will just mean I have to hard link in some more libraries from a read-only bind mount or some such thing. Maybe I'd even have to make truly real home directories for user dynamically added to /etc/passwd or something. It might add several milliseconds to the Firefox start time. Hopefully, if that happens, the Firefox developers will realize they have holes and get them fixed.
In any event, there's plenty more room to raise even higher walls between instances, even concurrently, of Firefox. We'll go where we need to go. There's only so far that the scumbag versions of web developers can go with this.
now we need to go OSS in diesel cars