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Tor Open To Attack
Posted by
kdawson
on Sun Feb 25, 2007 04:58 PM
from the peeling-the-onion dept.
from the peeling-the-onion dept.
An anonymous reader writes "A group of researchers have written a paper that lays out an attack against Tor (PDF) in enough detail to cause Roger Dingledine a fair amount of heartburn. The essential avenue of attack is that Tor doesn't verify claims of uptime or bandwidth, allowing an attacker to advertise more than it need deliver, and thus draw traffic. If the attacker controls the entry and exit node and has decent clocks, then the attacker can link these together and trace someone through the network."
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Well, not just that. (Score:5, Interesting)
This actually makes me wonder if there is a military/intel datacentre that does this already.
Re: (Score:3, Informative)
At which point the client seeks another route. Right?
What I'm saying is that I don't think this would be effective with only one or two nodes.
Though on a larger scale, I agree that this tactic could effectively DOS the network.
COMSEC, not SIGINT (Score:5, Interesting)
Probably, but not for the reasons you think. Tor is known to be used by the military (how much is anybody's guess) for the same reasons anybody else would use it.
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Re:COMSEC, not SIGINT (Score:5, Funny)
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Re:Well, not just that. (Score:5, Interesting)
No, but the Chinese equivalent of the FBI probably cares a lot about what its citizens are doing on the net, and the ability of users living under hostile regimes to get unfettered network access is one of the goals of projects like Tor.
There are people with resources besides the NSA.
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Re:Well, not just that. (Score:5, Informative)
If [dailykos.com] only [commondreams.org] that was true [sldn.org]...
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Re: (Score:3, Insightful)
Of course there are going to be police at protests. Blending in with the crowd just makes it easier to take care of things if an incident occurs. Is this supposed to be surprising, scandalous, conspiratorial? Because it's not. It's perfectly logical to anyone with a lick of sense.
This is from the second link of the GP:
The officers hoist protest signs. They hold flowers with mourners. They ride in bicycle events. At the vigil for the cyclist, an officer in biking gear wore a button that said, "I am a shameless agitator." She also carried a camera and videotaped the roughly 15 people present. Beyond collecting information, some of the undercover officers or their associates are seen on the tape having influence on events. At a demonstration last year during the Republican National Convention, the sham arrest of a man secretly working with the police led to a bruising confrontation between officers in riot gear and bystanders.
Perfectly logical? Really?
Not quite so oblig SW reference.. (Score:3, Funny)
"I felt a great disturbance in the Internet, as if millions of child-pornographers suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened."
Now now, I know Tor isn't just used for naughty stuff. I just thought it was funny. Sorta.
Re:Not quite so oblig SW reference.. (Score:4, Informative)
"Feb 25 16:16:02.628 [notice] Tor v0.1.1.xx. This is experimental software. Do not rely on it for strong anonymity."
Thus proving, once again, that Tor is only for the Quasi-anonymous group.
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welcome to the watchlist (Score:3, Funny)
So, ze kiddie porn is on vor mind, eh Social Engineer? Very interesting. Who besides grandstanding politicians, media whores and actual pedophiles actually thinks or talks about kiddie porn? You must be one of the bag guys. The FBI vill be watching everything you do for the next ten years.
In Soviet Russia... (Score:2, Funny)
How Many Nodes Do You Need to Own? (Score:5, Insightful)
3 to 6 servers out of 60 is still 5 to 10 percent. That's fine for small networks, but for a network with hundreds or thousands of nodes, controlling 5 to 10 percent may become infeasible. Does this attack require the number of nodes to scale with network size?
Re:How Many Nodes Do You Need to Own? (Score:4, Interesting)
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Anonymity Vs Performance in Multi-Hop Networks... (Score:5, Interesting)
It has been known for some time that anyone with the resources to do so could launch an end-to-end attack on Tor. That someone with relatively few resources could launch the same attack is newsworthy, perhaps, but far more interesting is the observation that optimizing network traffic flow in order to improve performance is the direct cause of this weakness.
Could this be avoided? (Score:4, Informative)
Re: (Score:2)
Re:Could this be avoided? (Score:4, Interesting)
Probably your best bet would be to use a spoofed MAC address, and change both the AP you connect to, the MAC address you report, and the PC's physical location, on a regular and frequent basis. That would make it difficult to determine whether you were a single location that's moving a lot and using different MAC addresses, or were multiple computers each just using the AP periodically.
Still, there's no foolproof way to avoid discovery against an omnipotent adversary.
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Re: (Score:3, Insightful)
Constant data stream (Score:4, Interesting)
Even if you can't become both the entry/exit... (Score:4, Interesting)
No love for Freenet? (Score:5, Funny)
Re: (Score:3, Informative)
As the above AC said, a lot of the discussion was on Frost, which doesn't have any publicly-accessible archives. You can find the mailing list thread here [freenetproject.org], though. In particular this [freenetproject.org] and this [freenetproject.org]
Of course, I'm not sure if this really matters that much; last I heard, Freenet was known to be vulnerable to man-in-the-middle attacks [freenetproject.org], and fixing it wasn't considered a priority...
Re:I for one.. (Score:4, Funny)
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Re: (Score:3, Insightful)
Re:WTFITOREH? (Score:4, Insightful)
To anyone not in the know, the fact that the TOR protocol has a weakness means absolutely NOTHING regardless of whether they know what TOR stands for or not.
Granted, there is such a thing as TLA-overload...but I don't think this is it. If you don't know that TOR stands for The Onion Router, then why the hell do you care whether it is vulnerable to attack or not? You obviously aren't using it... You don't care about the technology or implementation... You are apparently not even curious enough to Google it... So why bother clicking through to post such a rant?
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