10

check.torproject.org does not test the version of your TBB (Tor Browser Bundle). The test is performed by the TBB itself and the information is explicitly passed to the server. In the Firefox preferences check the Home Page setting. When TBB is up to date you will see: https://check.torproject.org/?lang=en-US&small=1&uptodate=1 when TBB is out of ...


8

Using such a system only prevents IP address leaks. The Tor Browser has many, many patches to reduce fingerprintability and fix privacy-breaking bugs. Think of it like this: Does it really help that no one can get your IP, if they can potentially link up all of your online identities? There are various and subtle ways of tracking a browser across the web ...


8

Except for reading through all of the plugin's or the extension's source code, there is unfortunately no way to make sure it is safe. And some believed-to-be-safe extensions like AdBlock Plus will still reduce your anonymity somewhat compared to other Tor users, by creating a more unique network fingerprint ("this user is the one that doesn't download the ...


7

There is two different levels on which you can be identified as a Tor or Tails user. It is not clear from your question which you means, so I will answer both. The website server you visit knows if you are using Tor or Tails Tails users can be identified as such by its browser fingerprint. For example, Tails comes with AdBlock Plus, and Tor Browser Bundle (...


7

Browser fingerprinting is the idea to have a unique set of property which can identify a browser. When you are visiting a website your browser identifies to the webserver. The site Whats my user agent shows you this information. Usually you'll find the operating system (Windows, Linux, Mac, Android etc.), the name of your browser plus the version and maybe ...


7

A browser fingerprint is a collection of info about a browser. When you visit a website, you send a variety of information, like screen size, installed fonts, and software versions; the site can also ask you for much more, as demonstrated by BrowserSpy. Like human fingerprints, browser fingerprints are usually unique. With your browser fingerprint ...


7

This approach of trying to shoehorn yourself into the middle of the bellcurve is ultimately destined to fail. Part of the problem is that you seem to be viewing each part of the various things they fingerprint on as a distinct challenge to approach and try and sit in the middle of the bellcurve of for all browsers. Instead, an observer knows you're using ...


5

I think those slides aren't about distinguishing tor users from non-tor users, they're about detecting Tor Browser Bundle users... so that they can serve the versions of their Firefox exploits that are tailored for that specific build of Firefox. Lots of people probably don't heed Tor Project's advice and use other browsers with tor, and maybe serving the ...


5

The developers of the Tor Project specifically recommend that you Don't enable or install browser plugins. Unless you're able to dig into the source code of the plugin yourself you'll never know what it's doing underneath. This particular plugin could do any number of presumably innocent things which could still expose your identity, including: It could ...


5

Every browser has a userAgent string that is sent to the remote server that tells it what browser and operating system is making the request. Tor is built on top of Mozilla Firefox. Firefox, and other Mozilla browsers, allow users to modify the userAgent string. In the address bar of the Tor browser, go to about:config A warning appears about voiding the ...


5

One possible solution is to disable the offending cipher by visiting about:config and setting the ciphers you don't want to false. Something like: security.ssl3.rsa_fips_des_ede3_sha false You could also improve your security by allowing TLS1.1 and 1.2 which are disabled by default in Firefox: security.tls.version.max 3 See my blog post ...


5

When using Tor the metadata provided by your browser (the data primarily used for fingerprinting) is only accessible to the server as all communication between you and the server is encrypted. If you were not using HTTPS, third parties between the tor exit node and the server would also be able to get the browser metadata.


4

Whether you can fool the site you are connecting to into thinking you are using a different browser depends on the method that the site uses to identify your browser. If the site identifies the browser by looking at the User-Agent string, then you can fool it by modifying the User-Agent string. If the site detects Tor users by checking whether the IP ...


4

To get a good understanding of the general problem, I recommend the paper Why Efficient Traffic Analysis Countermeasures Fail . It gives a good overview of why previous defence mechanisms are not sufficient. They also proposed a rather simple classifier called VNG++ which achieves good detection accuracy by only exploiting coarse features such as "total ...


4

Youtube does a lot of crazy stuff. It is not your normal HMTL5 video tag, there was actually some beta feature where you can try to ask google to send you only with Ogg+Theora, but then many of the videos show up as unavailable. If you look at the video tag itself http://w3schools.com/tags/tag_video.asp You will notice that the tag provides the dimentions, ...


4

The site is not quite right about the SSL_RSA_FIPS_WITH_3DES_EDE_CBC_SHA cipher. As I wrote in my blog post on configuring SSL in a secure way this is not a bad cipher. It offers the same security as other cyphers which are considered secure by the HowsMySSL-site. So it is not necessary to disable it. When you want to disable it, enter about:config in the ...


4

Some obvious anonymity fails: checking your Gmail, etc. logging into your Facebook account using a fake Facebook account, but friending your true-name friends tweeting your true-name friends having the same set of interests that you do as your true name Beyond that, it's prudent to firewall everything involving your true name from your anonymous activity. ...


4

CSS can also measure your window width and height and send it back to the server. See the demo here: https://arthuredelstein.github.io/tordemos/media-query-fingerprint.html


4

Panopticlick works by comparing your browser's fingerprint with what it has seen so far. So when you're the first or one of the first users that access it with a new version, it hasn't recorded data from other Tor Browser users yet. After a while, more people visit it using Tor Browser and you're not unique anymore.


3

check.torproject.org has a manually updated list of "recommended" Tor Browser Bundle versions. It is trivial to check TBB's version against this list. The Tor Browser Bundle's own version number is updated whenever any of its components are updated. The User-Agent string is not used at all. The actual version check is done by the Torbutton component.


3

Tor Browser uses several techniques that help to prevent the linking of sessions. These include Tor Browser forces cookies to be discarded at the end of the browsing session. Cookies are small pieces of data that websites use to keep notes on who you are. They are commonly used as a login token, or as an identifier for adveritsment companies to track you ...


3

Changing the default font size and family can make your fingerprint unique, so it's strongly discouraged. Many sites use JavaScript based font probing to fingerprint users by printing invisible strings with different fonts and then comparing the dimensions to that of fallback fonts [1, 2, 3]. Tor Browser limits the number of fonts a page can use, but it ...


3

Today, Tor is moving away from looking like TLS, with pluggable transports being the solution for censored users. Tor is moving to using stronger cryptographic primitives so looking like a browser is no longer the goal. Detecting Tor relays not behind pluggable transports is relatively straightforward. One of the ways is doing what you describe.


3

Tor browser user-agent strings at this point in time Dec-31-2014 for the current version is: Mozilla/5.0 (Windows NT 6.1; rv:31.0) Gecko/20100101 Firefox/31.0 In the past Tor browser has used many different user-agent strings, depending on which version of Tor browser you are interested in, one can search for that particular user-agent string.


3

Yes, A and B could collude and identify the two users as being the same person with a substantial certitude1. If one of them has access to identifying information (IP address, name, email, etc.), the other would have access to them too (as they are colluding). The most important part is, even if they don't have any identifying information, tracking your ...


3

Screen sizes differ between laptops, a hard set screensize would result on a browser that was too small for users on one system or too large to even display on other systems. Instead it picks a size that is some multiple of 200x100, with 1000x1000 as the maximum size, and uses that to pick an appropriate size to make the window, this provides a work around ...


2

While it is definitely very possible to see that the traffic is coming from an IP that is an exit node, regular traffic could possibly be coming out of the exit node as well. Despite the fact that the Tor Project suggests that you use a dedicated IP address (https://blog.torproject.org/running-exit-node #2) for your exit node, it is possible for the ...


2

Since you're using the default settings of Tor, most scripts are disabled by default (including JavaScript) by a browser add-on called NoScript. Yes enabling JavaScript would allow you to watch movies, but you'd also make yourself vulnerable to people finding out information that could be used to identify you.


2

No, they cannot do that, since all traffic is run through tor. Only way they can find that info is by compromising your laptop. You are as safe as any other tor user.


2

Configuring another browser to connect using Tor is reasonably easy. The more difficult problems are: Making certain that all the traffic goes through Tor, including DNS requests. Eliminating all the means by which your browser can reveal your real IP. Making the data revealed via javascript, browser headers, ETags, etc agree with each other without ...


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