Hacker News Reader

Comment by bauruine | Hacker News Reader

If they are able to do a deanonymization attack on the 3 hop Tor circuit why should a VPN protect you? They can just mount a similar attack on the one hop VPN.

View on HN

Thus the requirement for the VPN to be trustworthy.

What that means changes on the threat model, but for this scenario we'll say a hypothetical VPN provider in a different jurisdiction that takes Monero and has good OpSec.

The reason they can do the deanonymization attack on the Tor circuit is that they have basically unlimited resources to set up nodes, and Tor is built on the assumption that the nodes are all unrelated.

If a Tor session looks like:

    User -> VPN -> Tor( A -> B -> C ) -> Market

then the government could have the advantage of owning both A and B, or any other combination. That is difficult (though not impossible) to do to a VPN that they do not have jurisdiction over.

Anyone can set up a Tor node, but it's not possible to just randomly add nodes to a VPN's network, so they shouldn't be vulnerable to that (barring insecurity in other forms).

Check my other reply. I don't think you understand how deanonymization attacks work. It's not by governments "owning nodes." They might sometimes run the exit node, but that's for detecting certain activity, not finding people.

Plus, you can restrict what nodes are used. It's not like the public nodes are the only ones that exist.

Thanks, I appreciate it.

Clearly I've got gaps in my understanding, any good resources you could point me towards to study up?

I'd check out Wikipedia categories for general pointers. I think it's important to highlight that internet privacy and internet anonymity are two very different things. Also take care on how the word anonymous is used. Some use the word "pseudo-anonymous" which isn't the same thing.

It'd also be helpful to first learn how routing works. Then check out different types of applications(Tor, AnoNet, ZeroNet, etc) and read up on how they implement their networks.

Also read up on how the people who ran the markets got caught (read up articles in addition to Wikipedia).

Be aware Wikipedia shouldn't be used as actual fact. Check the sources. Many editors misinterpret them, or don't even read them at all.

https://en.wikipedia.org/wiki/Category:Internet_privacy

https://en.wikipedia.org/wiki/Category:Anonymity_networks

https://en.wikipedia.org/wiki/Routing

Some keywords/concepts that may help:

I2P/Peer-to-peer/Friend-to-friend/

Onion routing

Garlic routing

Digital fingerprinting

https://en.wikipedia.org/wiki/Mix_network

https://en.wikipedia.org/wiki/Crowds_(anonymity_network)

https://en.wikipedia.org/wiki/ZeroNet

https://en.wikipedia.org/wiki/Anonymous_P2P

Tails/Whonix/QubeOS for system protection.

Amazing, thank you.

The common misconception is that you have to run the nodes to do a traffic correlation attack. It's enough to see the traffic of the nodes e.g. on a IXP or as the ISP. [0] Even if the VPN is trustworthy and adversary that is able to break Tor could most likely still sees the traffic and can do a similar attack like he did for Tor.

I'm not saying that this happened only that if you think that there is a global adversary that can break the Tor anonymity a VPN won't protect you.

[0] https://www.ohmygodel.com/publications/usersrouted-ccs13.pdf

Reply on news.ycombinator.com