5 ms·

What are your thoughts on the integrity of the network against state actors?

alt227 3y ago
I assume that TOR is vulnerable to the 51% attack? If so I would imagine that state actors have the ability to spin up a million containers each hosting a node and easily take control (or at least be able to start tracing connection from entry to exit node). However Im sure this would be immediately obvious (unless they have been slowly doing this since the begining of TOR)
- bombcar 3y ago
  IIRC there is at least one known case where a moderately major criminal was let go rather than the government disclosing how they got the evidence on him. The assumption has been that they had a way of compromising TOR that they didn't want to reveal.
  - generalizations 3y ago
    One implication of that - make sure there's no available means of parallel construction, and it's ok if they catch you in some way they don't want to reveal. As long as you're not valuable enough, that is.
    - bombcar 3y ago
      That's the real bar for any security, really - make it so it's not worth the while of people who could defeat it. Because eventually, no matter what you do, if you're up against a nation state, they'll just make you dead.
susan_segfault 3y ago
There's a lot in the book about this - it depends what you mean. Tor has a lot of social and technical design elements that try as best they can to minimise this risk. It would be pretty hard for intelligence services to compromise the Tor organisation in ways that meant they were deploying malicious code, for example. Plus, the way it's grown over the years has also given them some protections. In terms of deanonymising people through surveillance (for example, by spying on the whole Internet and tracing you through the Tor network), Tor explicitly doesn't protect you against this. The decision was made early on - they switched all the high-security design elements to 'off' to make the network faster. They calculated that a hyper-secure network that was so slow no-one used it was less secure - i.e. made less privacy exist in the real world - than one that was less secure but used by millions, because that would give you a huge crowd of people to hide in. This gets really complicated - because you also want lots of different kinds of people using the network, so they can't tell if you're a drug dealer, an activist, a spy etc. just because you're using Tor. Individual bits of major intelligence organisations can probably deanonymise you at some times, and not at others. The real question is if they can do so in a way that's dangerous to you in a sustained way, and if it's actually useful for them to do this. Usually, it's easier to do this through simpler mechanisms (bribing your friends, putting a camera in your bedroom, figuring out who you are etc.) than compromising the Tor network. Some security services absolutely will be researching and developing ways to deanonymise larrge numbers of Tor users at a given time - but in general, the budget for this is going to be quite high on a per-user basis (so you'd have to be a prime target for it to be worth it), and a lot of the complexity of the Internet geography makes this quite hard itself. Ultimately, for any given high value target, there are usually easier ways to get them than through breaking Tor. In almost every case, a person will make a basic OPSEC error long before mass-scale traffic analysis gets them.
- htrp 3y ago
  The rubber hose cyptography xocd comes to mind https://xkcd.com/538/ https://xkcd.com/538/
- generalizations 3y ago
  The scenario that I understand is more plausible, is when state level actors might control some large fraction of tor nodes. Not that they have visibility into the entire internet (not ruling that out, though). The rule of thumb I've heard is that if you're a sufficiently valuable target, best assume Tor is compromised.
  - jazzyjackson 3y ago
    "don't become an enemy of the state" is my go-to security posture
    - geraldhh 3y ago
      same, though there are ppl that become so by chance or occupation
    - generalizations 3y ago
      I mean, the upstream question we're discussing is whether tor is appropriate if your threat model includes state actors.
    - barbariangrunge 3y ago
      What about whistleblowers?
    - llmblockchain 3y ago
      "don't become an enemy of any state" which is a little trickier.
  - belorn 3y ago
    Controlling a large fraction of tor nodes is possible, but there is a large cost associated with it. Tor has a reputation system when it comes to nodes, and in order to gain a large fraction of tor nodes you need to continuously have a presence for a long period of time. Having such long term presence also risk gaining visibility and become detected, and require good and consistent secops. As the network expands this also mean the attacker need to expand in equal rate. It is a assumed vulnerability of the network. The biggest question is if any state actor would consider it economical to do it compared to alternative methods. Personally I suspect that it is actually cheaper to have visibility into the entire internet, since that method bring value beyond tor and you do not need major secops to pull it off.

I assume that TOR is vulnerable to the 51% attack? If so I would imagine that state actors have the ability to spin up a million containers each hosting a node and easily take control (or at least be able to start tracing connection from entry to exit node). However Im sure this would be immediately obvious (unless they have been slowly doing this since the begining of TOR)

bombcar 3y ago
IIRC there is at least one known case where a moderately major criminal was let go rather than the government disclosing how they got the evidence on him. The assumption has been that they had a way of compromising TOR that they didn't want to reveal.
- generalizations 3y ago
  One implication of that - make sure there's no available means of parallel construction, and it's ok if they catch you in some way they don't want to reveal. As long as you're not valuable enough, that is.
  - bombcar 3y ago
    That's the real bar for any security, really - make it so it's not worth the while of people who could defeat it. Because eventually, no matter what you do, if you're up against a nation state, they'll just make you dead.

susan_segfault 3y ago

There's a lot in the book about this - it depends what you mean. Tor has a lot of social and technical design elements that try as best they can to minimise this risk. It would be pretty hard for intelligence services to compromise the Tor organisation in ways that meant they were deploying malicious code, for example. Plus, the way it's grown over the years has also given them some protections. In terms of deanonymising people through surveillance (for example, by spying on the whole Internet and tracing you through the Tor network), Tor explicitly doesn't protect you against this. The decision was made early on - they switched all the high-security design elements to 'off' to make the network faster. They calculated that a hyper-secure network that was so slow no-one used it was less secure - i.e. made less privacy exist in the real world - than one that was less secure but used by millions, because that would give you a huge crowd of people to hide in. This gets really complicated - because you also want lots of different kinds of people using the network, so they can't tell if you're a drug dealer, an activist, a spy etc. just because you're using Tor. Individual bits of major intelligence organisations can probably deanonymise you at some times, and not at others. The real question is if they can do so in a way that's dangerous to you in a sustained way, and if it's actually useful for them to do this. Usually, it's easier to do this through simpler mechanisms (bribing your friends, putting a camera in your bedroom, figuring out who you are etc.) than compromising the Tor network. Some security services absolutely will be researching and developing ways to deanonymise larrge numbers of Tor users at a given time - but in general, the budget for this is going to be quite high on a per-user basis (so you'd have to be a prime target for it to be worth it), and a lot of the complexity of the Internet geography makes this quite hard itself. Ultimately, for any given high value target, there are usually easier ways to get them than through breaking Tor. In almost every case, a person will make a basic OPSEC error long before mass-scale traffic analysis gets them.

htrp 3y ago
The rubber hose cyptography xocd comes to mind https://xkcd.com/538/ https://xkcd.com/538/
generalizations 3y ago
The scenario that I understand is more plausible, is when state level actors might control some large fraction of tor nodes. Not that they have visibility into the entire internet (not ruling that out, though). The rule of thumb I've heard is that if you're a sufficiently valuable target, best assume Tor is compromised.
- jazzyjackson 3y ago
  "don't become an enemy of the state" is my go-to security posture
  - geraldhh 3y ago
    same, though there are ppl that become so by chance or occupation
  - generalizations 3y ago
    I mean, the upstream question we're discussing is whether tor is appropriate if your threat model includes state actors.
  - barbariangrunge 3y ago
    What about whistleblowers?
  - llmblockchain 3y ago
    "don't become an enemy of any state" which is a little trickier.
- belorn 3y ago
  Controlling a large fraction of tor nodes is possible, but there is a large cost associated with it. Tor has a reputation system when it comes to nodes, and in order to gain a large fraction of tor nodes you need to continuously have a presence for a long period of time. Having such long term presence also risk gaining visibility and become detected, and require good and consistent secops. As the network expands this also mean the attacker need to expand in equal rate. It is a assumed vulnerability of the network. The biggest question is if any state actor would consider it economical to do it compared to alternative methods. Personally I suspect that it is actually cheaper to have visibility into the entire internet, since that method bring value beyond tor and you do not need major secops to pull it off.