Tor, NSA, GCHQ, and QUICK ANT Speculation

Many Tor users and various press organizations are asking about one slide in a Brazillian TV broadcast. A graduate student in law and computer science at Stanford University, Jonathan Mayer, then speculated on what this "QUICK ANT" could be. Since then, we've heard all sorts of theories.

We've seen the same slides as you and Jonathan Mayer have seen. It's not clear what the NSA or GCHQ can or cannot do. It's not clear if they are "cracking" the various crypto used in Tor, or merely tracking Tor exit relays, Tor relays as a whole, or run their own private Tor network.

What we do know is that if someone can watch the entire Internet all at once, they can watch traffic enter tor and exit tor. This likely de-anonymizes the Tor user. We describe the problem as part of our FAQ.

We think the most likely explanation here is that they have some "Tor flow detector" scripts that let them pick Tor flows out of a set of flows they're looking at. This is basically the same problem as the blocking-resistance problem — they could do it by IP address ("that's a known Tor relay"), or by traffic fingerprint ("that looks like TLS but look here and here how it's different"), etc.

It's unlikely to have anything to do with deanonymizing Tor users, except insofar as they might have traffic flows from both sides of the circuit in their database. However, without concrete details, we can only speculate as well. We'd rather spend our time developing Tor and conducting research to make a better Tor.

Thanks to Roger and Lunar for edits and feedback on this post.

Thanks. Several clarifications / follow-up points:

> I urge the Tor Project to think about countering the TAO

I think isolating various components (Firefox and Tor in particular) in their own separate VMs will go a long way here. However, the current Tor people don't have the right skills and time to make that happen in a usable, buildable, safe way. We need your (yes, you, the broader community) help.

> Roger suggested that concerned Tor users study the Tor-related papers at the freedom host archive

Please do not confuse with something by the name of 'freedom host'. :)

> So I hope that the Tor Project will work harder to provide a forum allowing anonymous posting via Tor connections

Yeah, me too. We have too few people, and spreading them over "make Tor better", "teach people how to use Tor more safely", and "set up forums and stuff" isn't working out great. We must grow -- that means you.

> I would remind them that for many years they resisted warnings from the user base [...] to update their thread model

I don't think that's a fair statement. Nobody knows how to build a usable network that handles the user base of Tor and provides better anonymity. It's not like we were saying "you folks are wrong, there's no need to defend against that". We were very aware that there are realistic threats we can't defend against. It sucks that that's the state of the technology and the research. (Did I mention you should help?)


September 18, 2013


Guys, I have a question/fear in my mind.
I host a tor hidden service, with some nasty content (no, not CP, but otherwise nasty.)

3 days ago my webserver is under some kind of an attack. Somebody (probably a robot) querying my website, once in a second(!), and always the same page. My log is now filled with these GET requests, every 1 or 2 seconds there is one.

These requests coming through the TOR network, firstly because it is originating from, secondly because if I shut down Tor, the requests also stopping.

I have a fear. Can it be connected to the NSA/FBI somehow? I mean, why the hell anyone wanna flood me with get requests? It's too slow for a DDOS attack (my website is fully operational).

And speaking of slow, how the hell can a TOR user request anything from my site every one or two seconds?
The TOR network by default is way slower than that. Even if I start pressing the reload button on Tor Browser, it takes 8-10-15 seconds to reconnect and reload the page. And yet, in my log files I see someone who can reload my page every 2 seconds, and does that over 3 days now.

Anybody knows what can it be?
Do I need to fear, is it something with the topic discussed here, or... or what?

Thank you!

My best guess is that it's a researcher trying to look at statistics for hidden services, what they serve, how available they are, etc.

But the next guesses should in fact worry you -- if I were trying to locate a Tor hidden service one of the components of my attack would be "access it frequently, to force it to talk frequently".

As for the speed thing, Tor actually has not-bad latency these days, if you can get your circuit built (using Tor 0.2.4.x will help a lot there), and if you're using a recent enough Tor Browser so it uses the optimistic begin cells:……

Another theoretical explanation to that could be a form of "tagging": the hidden server machine could be later identified, if this known pattern is found in some connection log.

To the "scared" operator: do you hear the cop cars pulling in the driveway yet? ;-)
Seriously, do us all a favor - don't use the Tor network for any nasty purpose. You'll sleep better.

Seems like a pretty funny-shaped tag. Why not stick a unique number in the user-agent, or the page it's asking for, etc? And then ask only once. That would be a much more robust, and much tinier, tag.


September 18, 2013


I'm afraid. What if you ll force to collaborate (and force to be silent by court)? This currently has happened to many american companies.

I answered this one here:

"We should all keep in mind that they can't force us to do anything. You always have the alternative of stopping whatever it is you're doing."

And I even wrote that before Lavabit et al. :/

To make it clearer, they will not force us to collaborate. And we won't stay silent.

You're right that it *has* happened to many American companies, and that sucks. It also means that those companies had different priorities than you and I think they should have.


September 18, 2013


Much of what has been discussed above is beyond my level of expertise at this time; however, thankfully you have already considered this and provided a way for those of who might feel still be able to participate and not feel quite so...well, dumb?

When I scrolled through comments and arrived at the bottom of the page...there it was...a simple addition problem and upon successful completion of said math problem. ..I found myself thev land of our most brilliant and technological geniuses. I could be proud. ..because I was now in the the party...and sitting at the cool guys table. It seemed as though all was right in the world...and I did belong here...even if...I only understood the math!

lol...thank you all for sharing your knowledge and expertise, as I am forever in your debt. Hopefully. will have gotten a smile from this...and continue to be patient, as we continue to listen to all you have to share. :-)

God bless...and Goodnight!


September 19, 2013


My comments are not appearing. Is the reason that I wanted to discuss the issue of the NSA internship?


September 19, 2013


Good job, but i'd like to say that the "guardianproject" that distributes the Android version of Tor is TOTALLY INCOMPETENT and it's can also be DANGEROUS to use, for some people:
the Tor version they distribute via their F-droid repo is DATED *2012* !!
And right now i noticed that the "switch user-agent" feature is buggy and LEAKS my phone model and the language if i choose "android" or "nokia" as user agents.

Please, torproject, be careful while choosing who distributes your software.
Guardianproject is seriously damaging the public image of Tor and the Torproject.
GP diistributes a (seemengly by purpouse) BUGGY AND INSECUREversion of Tor and is endangering the privacy of dissident in the world (remember: FULL dev name and real language leakage)

Written by a user that from now on will only use the PC version of Tor, since a SECURE Android version DOESNT EXIST right now

Actually, Tor is the current stable release of Tor, and we released it on 2012-11-19. So don't be upset with them about that.

If you want to be nervous about Orbot, be nervous that they don't include all the browser-level privacy fixes that Tor Browser has.

Confirm that Orbot/Orweb browser leaks my phone model, Android Version and build info in an added (by the browser itself) HTTP WAP header. That's ridiculous.

Further investigation shows that Orweb is leaking verbatim certain values from android build.conf if they are present into HTTP headers.. After a quick search I further note there are active bug reports in their system on this problem.

Seems Orbot/Orweb is very much a work in progress.

Would be good if there could be a hookup. The leaking headers (from Android's build.prop) bug reports seem to have been open for months so I'm not sure how much developer time they have available to work on problems.. Rooted phone users can remove the constants from build.prop as a workaround. I doubt anyone is really worried about WAP configuration these days.


September 19, 2013


Tails is developed at, but they currently provide no web feedback, so I hope the Tor developers will get some important feedback to them.

Please let the Tails developers know that on their download page, the detached signature for the Tails 0.20.1 iso (released 19 Sept 2013) points to the signature for the torrent (not the iso) and in any case both signatures appear to be missing!

Once this problem is fixed, anyone using Mac or Linux OS should be able to download

* the iso image
* the detached signature
* the signing key

and follow directions to

* import the Tails signing key into your local GPG keyring
* verify the detached signature
* burn a bootable DVD using the iso image

Windows users should keep in mind that there is no way to download GPG without using an unknown .exe. If possible they should obtain another live Linux distro such as Knoppix and use that to obtain Tails.

Another suggestion for Tails: consider an alternative detached signature using seccure with the maximal sized curve. This at least would avoid keyrings at the cost of requiring users to download and use seccure. I suggest it only as an alternative signature mode, not the default.


September 20, 2013


Is it not better to build a world with more LOVE!...many people and also people that have power are not filled with love but with HATE, they want to know what other people do and want to manipulate them.

What's wrong with those people?, we can build a better world with for example respect for other people's religion and other things in life.

We now mostly fight the symptoms but you will fight till infinity and that's taking a lot of energy, we can better give our energy to spread love and acceptance for other people..(win win situation)


September 20, 2013


This is a huge media blow to Tor, more like a scandal revealed to the general public whom often do not read any further than Tor's front page which states "Tor prevents anyone from learning your location or browsing habits".

There are no clear warnings on the front page of Tor's limitations and that is made intentionally to promote the project, and this worked quite a while for overly excited lazy people.

For the more experienced, the weaknesses have been long known, so there isnt much of a surprise there. The NSA is too much ahead of Tor, so if you are up against them it would be wise to stop using the internet.

Hope this comment isn't too much for anti-censorship claiming fellas and would actually make it unscathed.

Yeah, if the NSA is targeting you, "stop using the Internet" is a very reasonable step. Tor isn't going to help much. And there are many other technologies you should stop using as well.

We used to have a pile of warnings on the download page, about anonymity risks. They're still there:
but they've been simplified over time because too many users were confused.

Our website is definitely suffering from trying to be understandable by too many audiences.

My rough plan for resolving this, short to medium term, is:

A) Finish my blog post about why we need to raise the guard rotation parameters, which should improve anonymity a lot against these large-scale adversaries. Oh, and start to actually take the steps I'll suggest.

B) Go through the new FAQ entries that Matt merged in from the wiki faq, and try to make them accurate and useful again.

C) Write a FAQ entry, or maybe a new page, explaining what anonymity properties Tor can and can't provide, including pointers to attacks that are known in the research literature. I worry that step 'C' by the time it's done will produce something hard for the normal user to understand. I guess we'll see.


in red, caps, bold, and at a clear spot on the front page is simple enough

That is if being honest surpasses the need for misleading marketing

Well, for one because that's a false statement too.

Notice that I said "if they're targeting you" above. Then they bust out the TAO team and it no longer matters that Tor is in the picture.

I think there are some user scenarios where Tor helps a great deal even against large scale surveillance like the kind NSA is doing.

And some cases where the large scale surveillance is in the right places, and assuming they do their math well enough they can link you to your destinations.

I'd rather try to explain the underlying issues that people need to consider, since no single sentence is going to be the right thing to say.

It's complicated by the fact that every time we do anything public like that we get swamped by journalists who write partially accurate articles and cause more journalists to swamp us. (And the 'us' is the Tor developers, so we're trading off fixing the actual problems in Tor for trying to correct press articles.) That happens in large part because we got behind on explaining research results to everybody, and so now they're shocked and excited every time they hear from us. Bad cycle to be in. Hopefully I will get to my plan in not too long and then I can stop trying to explain why I haven't gotten there yet.

I'd like to add another voice of appreciation to arma's work here.

The crush he describes of being caught between press/media outreach and "doing real work" is one that anyone on the front lines knows all too well. It would seem he's experiencing it, along with the rest of the Tor folks, at an almost unimaginable level.

It is indeed a Good Thing to patiently talk with the press - who are actually human beings, individual people - to help them understand how all this works and why it matters. It also takes an enormous amount of one's time - far more than it would seem to those who read the articles and see a quote or two, nothing more. Almost without exception, that was a few hours' time talking with the reporter and that work is invisible to the public eye.

But to say "too busy for you press folks, go away!" is also simply not an option as they will write their stories anyway, but the stories will be even more technically inaccurate as a result. And people rely on the press - normal, nontechnical folks - to tell these stories. If we just wash our hands of the press, then we're washing our hands of most human beings using the internet, period. That is not an option.

Folks with the expertise and professionalism of arma could be, let us not forget for a minute, making vast sums of money working for Vupen or some other cyberwar drum-beater: stable hours, no political pressure, executive assistant to open the mail and bring coffee... honestly, this is the alternative for talented folks. That he is working to make Tor as good as it can be, with all the other pressures, is a testament to an integrity of spirit and true dedication.

As we say elsewhere, this recent round of anti-Tor hits does not seem at all to be just a random confluence of events. Not to us. For those with experience in the darker sides of how folks with power strike back against those who threaten them, this is all of a piece. And arma is doing his absolute best to handle it all whilst still producing quality code & managing a team of talented folks working on some not-simple technical challenges. This is an extraordinary burden to be carrying.

We may not always agree with how "Tor" is doing this or that - and I personally may have my own views on this or that - but that is all picayune relative to the respect the Tor folks have long-since earned from all of us. Tor is facing an organized, multi-pronged, dirty-war disinfo/extra-legal harassment campaign right now and so far they are (in my opinion) weathering it with courage, competence, integrity, and wisdom. There is much to learn from their handling of this round of attacks thus far.

There is also a need for all of us to thank them for what they do.

~ pattern_juggled |

there has been no mention of Whonix as far as I can tell. Having an open OS wthin a VM is a great way to prevent a large chunk of how NSA/GCHQ resolves a users identity/location. From what I've read they rely heaily on exploits and hacks.

I mentioned it in……

Whonix needs more people looking at it, and being able to build it also, before we can comfortably recommend it to a larger audience. The idea is good, but that doesn't mean enough about the implementation.

Ok, I added this statement at the top of the announcements:

"It may be that Tor can't protect you against the NSA's large-scale Internet surveillance, and it may be that no existing anonymous communication tool can. We're working on writing clear explanations for the issues."

Can it be said better?

(I also took the opportunity to tidy up some other big words on the page.)


September 20, 2013


I make some observations and pose questions.

I don't see evidence in the media of people (I suppose that is mainly journalists) thinking through the consequences of the NSA/GCHQ revelations. Now that the Jo Public knows what technically savvy people have long suspected I would expect action to be added to outcry. We now know what only a dedicated conspiracy theorist hitherto would opine. We know that some software/hardware manufacturers have connived in the insertion of "back doors" and that others have unwittingly been compromised.

So, my first question is why isn't there a stampede of people trying to rid themselves of closed source proprietary software, not just operating systems but that which runs on them too? The person who just does a bit of web surfing and social contact via "social media" probably isn't too bothered that their activities will bore the socks off human operatives at NSA/GCHQ.

Professional people, particularly those holding records about individual "clients", whether at the office or at home, should be seething with anger and avidly seeking means of greater security. Large businesses should be worried about the safety of their legitimate commercial secrets. Such businesses have ready access to IT staff and I would imagine that board rooms seethe with anxiety and urgency; if so, no hint has been published.

As a number of organisations has found, e.g. the French police force, the initial costs of transition to open source software are vastly offset by long term saving on unnecessarily bloated, leaking like a sieve (regardless of NSA actions), costly software and by stepping off the treadmill of proprietary upgrades.

Similarly, what idiot would "upgrade" to Windows 8 installed on a machine with a special (hackable from outside) DRM chip on the custom made motherboard?

Perhaps complacency rules. However, I suggest that everyone reading this divest from shares in companies that rely on income from closed source software. Goodbye Microsoft, goodbye Apple and goodbye Adobe? Closed source software will become a thing of the past. Community supported (and checked) software will dominate. In future people will laugh at the notion of software patents and intellectual property (though attribution should remain).

I was with you until the very end. It's not clear to me that stock market performance has much at all to do with technical quality of the company's products.

"Teach your friends why closed and proprietary software is so dangerous" would maybe have a much bigger effect.


September 21, 2013


blame it on the drugs!! (everything else is and it is the only subject in the world that is treated as voodoo. e.g. tor project may have fallen into a giant k-hole?


September 21, 2013


anonymous34 said...and i quote nsa stands for national.stupid.apartite!.. is this true or am i being obtuse? (personaly i support all government agencies as they only have our interests at heart) we need to be told what to do for our own good! if not it is anarchy, isn't it? and as long as its not my human rights violated-'who cares?' as my daaddy would say.

all government agencies as they only have our interests at heart

sounds like the apple didn't fall far from the stupid tree. ignore if /s but it didn't sound like /s

Nsa + Facebook = Stasi2.0
They *alter* user traffic injecting *malware* to own user computers!…

you're sarcastic here, but the problem is that people with such 'naive' thought to believe that:

"personally i support all government agencies as they only have *our* interests at heart"

really exist!

The sourveillance apparate has *always* followed *only* big corporations agenda.

just a note:
"[...] if not it is *anarchy*, isn't it"

i dont know what you think *anarchy* is, but if you really think it's something to have fear about ... i suggest you read something serious about it, like Petr Kropotkin, Errico Malatesta, just to start.

"Common" people have nothing to fear about anarchy 'cause it's a social model/organization based on freedom *and* equality.

("common people" = people that are not part of the top of the pyramid, aka "not at the guide of the corporations")


September 22, 2013


Why not think of all the good things about TOR? It is used in some countries that people are not allowed to have freedom of speech and would be tortured/killed for speaking out. It seems a few people using sites that had illegal content are annoyed at somehow being "tricked". There are many warnings about TOR. How many people used programs to download files for example? Those programs could have "phoned home" or stored information to reveal what users had done.
It is possible that GCHQ, NSA, FBI, MI5/MI6 and whoever else is involved can decrypt and read data and identify users. TOR is not a tool to use for breaking the Law! It will not protect you.

I was with you until the last sentence.

I'd love to live in a world where "the law" was universally agreed upon and only good laws existed. Actually, on second thought, maybe I don't want to live in that world either. In any case, there is no single "the law" to look at.

(To give you a concrete example, consider "the law" in Pakistan against using VPNs.)


September 23, 2013


something i forgot to say all the time ...

thank you arma and god bless u



December 31, 2013


Getting philosophical, what is a law but one man's ideals forced upon another's rights. Just kidding. I think Tor is a great tool if you need to have un-compromised internet