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Tor Users Urged To Update After Security Breach
An anonymous reader writes "If you use Tor, you're cautioned to update now due to a security breach. In a message on the Tor mailing list dated Jan 20, 2010, Tor developer Roger Dingledine outlines the issue and why you should upgrade to Tor 0.2.1.22 or 0.2.2.7-alpha now: 'In early January we discovered that two of the seven directory authorities were compromised (moria1 and gabelmoo), along with metrics.torproject.org, a new server we'd recently set up to serve metrics data and graphs. The three servers have since been reinstalled with service migrated to other servers.' Tor users should visit the download page and update ASAP."
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Anyone else find it so funny that a news story about anonymity is suggested to slashdot by anonymous coward?
I think it's the best form of joke... one with an epic amount of unexpected expectedness.
quoi?
They feared that it could be used to suppress protest or support unpopular rule.
How many child porn downloaders and uploaders are shitting their pants right about now? My guess is more than spies and Chinese dissidents.
Those who can, do. Those who can't, sue.
Anyone else find it so funny that a news story about anonymity is suggested to slashdot by anonymous coward?
I think it's the best form of joke... one with an epic amount of unexpected expectedness.
If you think that's funny, just think...
Every Anonymous Coward posting about this article will be an Anonymous Coward posting about an Anonymous Coward's anonymity story. A story by an Anonymous Coward for Anonymous Cowards about Anonymous Cowards. Anonymous anonymous anonymous.
The problem with Tor is that there's no way to detect compromises -- every node on the network could be compromised and you'd never know. Authors of botnets have greater anonymity than we do -- ironically because it's run by a central authority. An illegal and immoral one, yes, but one that comes with a measure of anonymity. Few botnet authors are actually caught even with the most primitive security methods. They don't even use encryption and they often can't be found...
#fuckbeta #iamslashdot #dicemustdie
Roger's entries to date on the subject (excluding first page linked within /. summary):
(this is for those who are too lazy to page through mailing list threads, this post is
missing other individuals replies as well as future replies from Roger and others)
http://archives.seul.org/or/talk/Jan-2010/msg00165.html
Here are some more technical details about the potential impacts, for
those who want to know more about Tor's innards:
----- #1: Directory authority keys
Owning two out of seven directory authorities isn't enough to make a new
networkstatus consensus (you need four for that), but it means you've
only got two more to go. We've generated new v3 long-term identity keys
for these two authorities.
The old v3 long-term identity keys probably aren't compromised, since
they weren't stored on the affected machines, but they signed v3 signing
keys that are valid until 2010-04-12 in the case of moria1 and until
2010-05-04 in the case of gabelmoo. That's still a pretty big window,
so it's best to upgrade clients away from trusting those keys.
You should upgrade to 0.2.1.22 or 0.2.2.7-alpha, which uses the new v3
long-term identity keys (with a new set of signing keys).
----- #2: Relay identity keys
We already have a way to cleanly migrate to a new v3 long-term identity
key, because we needed one for the Debian weak RNG bug:
http://archives.seul.org/or/announce/May-2008/msg00000.html
But we don't have a way to cleanly migrate relay identity keys. An
attacker who knows moria1's relay identity key can craft a new descriptor
for it with a new onion key (or even a new IP address), and then
man-in-the-middle traffic coming to the relay. They wouldn't be able to
spoof directory statements, or break the encryption for further relays
in the path, but it still removes one layer of the defense-in-depth.
Normally there's nothing special about the relay identity key (if you
lose yours, just generate another one), but relay identity keys for
directory authorities are hard-coded in the Tor bundle so the client
can detect man-in-the-middle attacks on bootstrapping.
So we abandoned the old relay identity keys too. That means abandoning
the old IP:port the authorities were listening on, or older clients will
produce warn messages whenever they connect to the new authority. Older
Tor clients can now take longer to bootstrap if they try the abandoned
addresses first. (You should upgrade.)
----- #3: Infrastructure services
Moria also hosted our git repository and svn repository. I took the
services offline as soon as we learned of the breach -- in theory a clever
attacker could give out altered files to people who check out the source,
or even tailor his answers based on who's doing the git update. We're
in pretty good shape for git though: the git tree is a set of hashes
all the way back to the root, so when you update your git tree, it will
automatically notice any tampering.
As explained in the last mail, it appears the attackers didn't realize
what they broke into. We had already been slowly migrating Tor services
off of moria (it runs too many services for too many different projects),
so we took this opportunity to speed up that plan. A friendly anonymous
sponsor has provided a pile of new servers, and git and svn are now up
in their new locations. The only remaining Tor infrastructure services on
moria are the directory authority, the mailing lists, and a DNS secondary.
----- #4: Bridge descriptors
The metrics server had an archive of bridge descriptors from 2009.
We used the descriptors to create summary graphs of bridge count and
bridge usage by country, like the ones you can see at
http://metrics.torproject.
now the cia + barack obama know i was browsing cp
How do you update a Tor SF paparback book?
I mean. That's where I'd go fishing for people trying to communicate secrets,
if I was them.
Now I don't want to spread paranoia, but
did you know that the patent on Onion Routing was filed by the US Department of the Navy?
Look it up.
Remember kiddies. Always use your own encryption layer.
Where are we going and why are we in a handbasket?
the chinese did it.
Attacking Tor at the Application Layer
http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-gregory_fleischer-attacking_tor.pdf
https://media.defcon.org/dc-17/video/DEFCON%2017%20Hacking%20Conference%20Presentation%20By%20Gregory%20Fleischer%20-%20Attacking%20Tor%20and%20the%20Application%20Layer%20-%20Video%20and%20Slides.m4v
https://media.defcon.org/dc-17/video/DEFCON%2017%20Hacking%20Conference%20Presentation%20By%20Gregory%20Fleischer%20-%20Attacking%20Tor%20and%20the%20Application%20Layer%20-%20Slides.m4v
https://media.defcon.org/dc-17/audio/DEFCON%2017%20Hacking%20Conference%20Presentation%20By%20Gregory%20Fleischer%20-%20Attacking%20Tor%20and%20the%20Application%20Layer%20-%20Audio.m4b
Sniff Keystrokes With Lasers/Voltmeters - Side Channel Attacks Using Optical Sampling Of Mechanical Energy And Power Line
Leakage:
http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-barisani-bianco-sniff_keystrokes.pdf
http://www.defcon.org/images/defcon-17/dc-17-presentations/Andrea_Barisani-Daniele_%20Bianco/defcon-17-barisani-bianco-sniff_keystrokes-wp.pdf
https://media.defcon.org/dc-17/video/DEFCON%2017%20Hacking%20Conference%20Presentation%20By%20Andrea%20Barisani%20and%20Daniele%20Bianco%20-%20Sniffing%20Keystrockes%20with%20Lasers%20and%20Voltmeters%20-%20Video%20and%20Slides.m4v
Router Exploitation
http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-fx-wp.pdf
https://media.defcon.org/dc-17/video/DEFCON%2017%20Hacking%20Conference%20Presentation%20By%20FX%20-%20Router%20Exploitation%20-%20Video%20and%20Slides.m4v
https://media.defcon.org/dc-17/video/DEFCON%2017%20Hacking%20Conference%20Presentation%20By%20FX%20-%20Router%20Exploitation%20-%20Slides.m4v
Unmasking You
http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-abraham-hansen-unmasking_you.pdf
Tactical Fingerprinting Using Metadata, Hidden Info and Lost Data
http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-alonso-palazon-tactical_fingerprinting.pdf
Down the R
IMHO sending a message inside a birthday card draws a LOT less attention than using obscure and suspicious looking encryption software. But thats just my opinion.
Only the State obtains its revenue by coercion. - Murray Rothbard
Mmmm, yes, free.
And you will never, in a million years, detect the compromised hardware in those machines.
The only way for tor (or wikileaks or other dangerous-to-the-authorities service) to buy hardware, is anonymously. If someone wants to donate servers, have them sell the servers and give you the cash.
FATMOUSE + YOU = FATMOUSE
"A friendly anonymous sponsor has provided a pile of new servers, and git and svn are now up in their new locations."
Am I the only one to find this suspiciously timely? Did the "anonymous sponsor" guarantee that none of the onboard chips/chipset were made in China or tampered with?
I think I just stopped using Tor.
While you have a perfectly valid point, your comment defending pedophiles now stands completely without context, as pretty much all of comments leading to it remain 0-score.
I'm not sure whether to congratulate your courage in posting with your account or assume it was an accident and offer condolences.
May be they trying to enter adult content industry...
Wait... Anyone can be a TOR node and it's still secure.
TOR data is very encrypted.
It doesn't matter if the hardware or software is compromised, it's still secure because a TOR node is just one node in a chain of encrypted nodes. You encrypt your data 5 times if you're sending it through 5 nodes.
Each node takes off one layer of encryption and forwards the still encrypted data to the next node. If any intermediate nodes (2 3 4 in our 5 node example) are compromised (in software or hardware), they can not see the message in plain text, or determine the originating IP or destination IP of the traffic.
If the first node is compromised it can see your source IP, but not the destination IP or any part of the message (it's still encrypted.)
If the exit node is compromised it can see the destination IP, and clear text message, but not the source IP.
These multiple layers of encryption mean that if any one node is compromised the system is still very secure.
Taking off a layer of encryption at each router is like peeling an onion... hence, "The Onion Router".
(this is an oversimplified explanaion -- if you're talking compromised code repositories, viruses and trojans are usually not delivered as source code, the tampering would be evident.)
I wish the holier than thous behind the Tor movement would stop with their outrageous and indefensible claims about the protections Tor allegedly provides.
I tried to have this discussion with, among others, people who've made "names for themselves" traveling from conference to conference blustering about how Tor is making the Internet safe for unpopular opinions in places where an unpopular opinion can get you disappeared right quick (hello China)... shouted down every time because it's not a POPULAR point of view.
I see that I'm not the only one in this discussion with concerns. Thank god things are changing.
I doubt that FBI, NSA, CIA, GRU, etc. all share their nodes with each other. As such, it is reasonable assumption that each node only belongs to one (or two at most) intelligence agency.
Now, if there are enough of such agencies, each controls so small partition of the nodes that it isn't a problem. On the other hand, if one agency has a wide control over the network, it means that the other agencies have very limited control. That leads us to a situation where Tor is useful against all but one agency, which isn't that shabby either.
There are some problems - it might be that all nodes in russia are controlled by GRU (though I really doubt CIA would let that happen) - but most of such are negated as long as the routing goes through nodes in several countries.
Attacking Tor at the Application Layer
Nothing really new here, just ordinary application attack vectors. Change habits accordingly to counter these exploits. Most scenarios assume application is FireFox/HTTP.
Sniff Keystrokes With Lasers/Voltmeters - Side Channel Attacks Using Optical Sampling Of Mechanical Energy And Power Line Leakage:
Assumes physical location has already been found, not really a valid assumption in most scenarios. Assumes PS/2 HIDs etc. and as the presentation says can be defeated by implementing TEMPEST protection.
Router Exploitation
Presentation only covers Cisco IOS issues, thus only applicable in environments which deploy them. Even then, some of the issues outlined aren't that relevant in regards to the use Tor.
Unmasking You
Again, nothing new. Change your habits accordingly in regards to the configuration of your system. Encrypt your connections using proper effective mechanisms for key distribution etc. which are relevant to what you are doing.
Tactical Fingerprinting Using Metadata, Hidden Info and Lost Data
Yet again nothing new, use open and minimal formats and strip your metadata. This isn't even a problem with Tor itself.
Down the Rabbit Hole: Uncovering a Criminal Server
I don't even see how many of the issues raised here are directly relevant to Tor, the issues raised have available counter measures anyway. Change your habits accordingly.
So basically, the issues you've raised are either already known with counter-measures available or aren't even directly relevant to Tor. Tor is a tool, it is said repeatedly that it doesn't automagically protect you, you have to use it correctly.
By the way, Lizard says "Hi" ^.^
TOR apologists, no fair modding down these comments just because you don't like them.
I wish the holier than thous behind the Tor movement would stop with their outrageous and indefensible claims about the protections Tor allegedly provides.
I tried to have this discussion with, among others, people who've made "names for themselves" traveling from conference to conference blustering about how Tor is making the Internet safe for unpopular opinions in places where an unpopular opinion can get you disappeared right quick (hello China)... shouted down every time because it's not a POPULAR point of view.
I see that I'm not the only one in this discussion with concerns. Thank god things are changing.
If Torbutton installed it and verified it was working correctly that would really help it to spread. Still, the bundles help.
The bigger problem is that Tor is hardly deniable. Your traffic might be secure, but in many circumstances the fact that you are sending secure traffic is far more interesting. Given the right circumstances, that enough is sufficient for the state to use rubber hose cryptanalysis...
[FUCK BETA]
Yes, but at the top is some form of directory service. If you compromise the majority of those servers you can create a new network consensus, and direct everyone to route through tor1,tor2...torX.nsa.gov. Or some suitable set of apparently random international network of nodes set up for the purpose. The layers don't work if the entire onion is rotten.
Live today, because you never know what tomorrow brings
"A friendly anonymous sponsor has provided a pile of new servers, and git and svn are now up
in their new locations"
I read this to mean that tor are hosting git and svn on the new, anonymously-donated servers. I expect that if they were hardware-compromised, that could be used, in turn, to compromise the source-repositories. Please correct me if I'm wrong tho...
Having said all that - I'd also expect a project like tor to be pretty careful with security! Also, it's quite possible that although the servers were anonymously-donated, they may still have been sourced by the tor project - it's hard to imagine a guy in a trench-coat and dark glasses knocking on their door, handing them a server before fading into the shadows, and them welcoming it with open arms!
This is torrible news! The torror...
You don't seem to have read the GGP post at all.
It lists plenty of venues of attack for a suficiently willing and knowledgeable attacker which state agencies would be.
I wouldn't so easilly dismiss attacks delivered via source code if I was you: the GP was talking about attacks by state security services - these guys usually employ full time some pretty clever people who can usually make their own code they're no just a bunch of script kiddies downloading tools from the Internet (although from the Google attacks I suspect that, like in many other things, the Chinese went for quantity over quality and a lot of their "State Hackers" are little more than script-kiddies). Understanding and subtly altering a code base is not that hard if you're an good and experienced programmer.
State agents thus have both the resources and the willingness for impersonating a friendly interested party, providing free machines that are actually compromised at the BIOS or even hardware level and subtly compromise TOR via the source code once the Source Control repository gets put in one of the trojaned machines - some of them might even have a wise enough leadership that they're willing to go slowly and carefully infiltrate and take over the TOR system using techniques like this.
A better proxy VPN?
If the exit node is compromised it can see the destination IP, and clear text message, but not the source IP.
So, collect enough packets at a compromised exit node and you can build a usage pattern with possibility of identification? Using Tor to check email or blog from oppressed nations just looked a little less appealing.
Finally had enough. Come see us over at https://soylentnews.org/
I'm not sure if you're not misunderstanding the purpose of Tor. Well, either that, or I am. :)
In any case, the purpose of Tor is not encryption but anonymity. This bears repeating: unless you take additional steps to encrypt the data sent through Tor, it WILL be plainly readable at some point. Intermediate nodes won't be able to decrypt it, obviously, but the exit node will see it, for obvious reasons.
The only thing the exit node doesn't know is who actually made the request, although this could quite possibly be inferred from the data being sent.
You should ALWAYS encrypt data sent through Tor.
Using tor to transmit anything unencrypted is a very DUMB thing. You have to understand that between the exit node and the target server, all traffic is done in the same fashion it would be done between you and the target server if you didn't use tor. If there is no inherent encryption (like https or ssh), it will NOT be encrypted between the exit node and the server.
In other words, it is trivial for someone who wants to sniff passwords to establish an exit node and just collect packets.
tor is NOT an encryption tool. It is a tool to mask your whereabouts, to give you the means to access information your government does not want you to see. It's a tool to avoid prosecution when you access "illegal" information (read: information your government deems illegal). It is NOT a tool to increase your security against MITM sniffing. Quite the opposite.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
The links are not very informative about what allowed the breach to happen. Was a security model vulnerability? man-in-the-middle attack? buffer overflow?
If the exit node is compromised it can see the destination IP, and clear text message
A lot of people put to much faith in TOR anonymizing capabilities, and forget this one little detail: If you are using an insecure transport method to begin with (ie: FTP, POP3, SMTP) you are still vulnerable to an attack from someone running a compromised exit node. Sure, it won't be direct, but it wouldn't be to hard to run a node and gather user names and passwords, and that can easily lead to figuring out who you are.
In other words: TOR is NOT A SECURE COMMUNICATIONS CHANNEL!!! It doesn't have any magical properties to keep plain text communications away from a random attacker. If you want to be secure, you must use a secure protocol!
Fighting oppression has always gotten people killed. If Tor allows people to speak out with less risk, it's done it's job.
Give me Classic Slashdot or give me death!
FTA: "A friendly anonymous sponsor has provided a pile of new servers ..."
Hairs standing on the back of my neck.
Good point. Bang on.
Now as we move to encrypted fragmented cloud storage and computing, that assumption will presumeably have to change, as it will become routine to encrypt both your stored content and its transmission. And I can see anonymization being offered as part of cloud services of the future, to prevent corporate espionage (shady forms of "business intelligence") etc.
When encryption and anonymization of net communications becomes the norm, then who do you watch, and how?
Where are we going and why are we in a handbasket?
Though the looking glass, Alice wrote:
Dear Trusting Fools,
I invited the jabberwocky and his friends into the white rabbit's house where I'm staying and he slipped something into the sauce. It's for your own good, you know.
Love,
Alice
++
The note is slipped through the looking glass and on the other side it reads:
Dear Friends,
Goodness! I've had some troubled times here in Wonderland, but everything is resolved and it has nothing to do with the sauce, everything is fine!
Love,
Alice
PS. I have a whole new batch of sauce you really should try! We're switching to the new batch now, we urge you to switch, too, for the sake of your health! We've added new vitamins!
You're right. We had better just give up.