Isn't Tor dead? Wasn't it infiltrated long ago?
If you want to avoid global passive adversaries, a mixnet like Nym can work. I'm also working on a related project which takes a different approach of building your own circuit of proxy servers manually with lots of traffic padding: https://github.com/markasoftware/i405-tunnel
Onion endpoint sites use encrypted traffic and the padding strategy, too and are still susceptible to the correlation attack.
There's a security blog that publishes research papers on different attack models. It's a total PITA to find but I'll see if I can locate it.
edit: JFC... finally found it: https://www.freehaven.net/anonbib/
Correlation attack concept: https://www.ndss-symposium.org/wp-content/uploads/2024-337-p...
Attack against Mixnet and Nym: https://petsymposium.org/popets/2024/popets-2024-0050.pdf
Nym/Loopix (and I405, though it's so experimental I feel bad even talking about it) completely defeat end-to-end correlation attacks, where an attacker tries to find statistical similarities between the encrypted traffic on the first hop (from the user's home network to some proxy), and the final hop (from some proxy to the final destination clearnet site).
Tor is trivially vulnerable to end-to-end correlation attacks. In addition to the paper you posted, my favorite is http://petworkshop.org/2007/papers/PET2007_preproc_Sampled_t... , which describes how an adversary monitoring just a small fraction (<0.1%) of traffic at key internet exchanges could deanonymize many Tor users.
Nym/Loopix and I405 defeat end-to-end correlation attacks with the same basic idea: Send fixed-rate traffic on the first hop, regardless of whether the user is actually trying to send any tunneled traffic. Both sample from a statistical distribution to decide when to send the next packet, and they send an empty packet if there is no actual data to send. In this way, the traffic being sent on the first hop does not depend at all on the inner cleartext data the user is sending/receiving.
The Mixmatch paper, which AFAIK is the only published attack against Nym/Loopix, is NOT an end-to-end correlation attack. It relies on the attacker controlling one or more Nym "gateways" (equivalent of guard nodes in Tor) and therefore being able to decrypt traffic from users whose first hop goes through that gateway. Further, I believe that the attack described in this paper becomes increasingly difficult as the number of users increases, and the authors of the paper include Nym developers who are actively making changes to make this attack harder. It's not a fundamental weakness in Nym/Loopix, the way that E2E correlations are for Tor.
That being said, yes, feds can de-anonymize traffic, probably reliably at this point. There are only about 7-8000 active nodes, most in data centers. The less nodes you hop through, the more likely that traffic can be traced back to the entry point (guard node), and combined with timing can be reasonably traced back to the user. Tor works best with many, many nodes, and a minimum of three. There's not as many nodes as there needs to be so quite often it's only 3 you are going through (guard node/entry point, middle node, exit node)
Plus browsing habits can also be revealing. Just because someone is using Tor doesn't mean they also have disabled javascript, blocked cookies, aren't logging into accounts, etc.
There have been some cases where some consider the "other lapses in OpSec" to be parallel construction to disguise a Tor vulnerability/breach, and others where the government has declined to prosecute because they'd have to reveal how they know.
If Tor were compromised, we'd likely not know. It's highly likely that it's fine for "normal people" things.
... now my back hurts and I want the damn kids off my lawn.
The tor project has network stats on their website: https://metrics.torproject.org/networksize.html
Looks like about 8,000 relays, inclusive of entry and exit nodes. Looks like about 2,500 exit nodes, and ~5,000 guard nodes. With that few I'd say it's reasonable to assume that a large number of both entry and exit are controlled by government agencies, at least enough to reliable to conduct timing attacks against a specific target they are interested in.
It's a little ambiguous.
Section 230 (which continues to be under attack) provides some legal immunity, along with the DMCA is a safe harbor against copyright infringement claims for the Tor relay operator. Running a middle relay is generally fine and safe.
But, running an exit relay is risky. Even if you can't be held legally liable for the traffic coming from the exit, you could still get raided, and it has happened before where exit node operators have been raided after the traffic coming out of it was attributed to the node owner.
That being said, it's legal to run an exit node (for now). The problem is more so dealing with the inevitable law enforcement subpoenas or seizures, and having the money and resources to prove you are innocent.
I can't find a link, but I think people have done simulations and the privacy benefits of more hops are not as great as one might think. If you control the guard and exit, then traffic confirmation is relatively easy by just looking at timing and volume of traffic no matter how many hops are in between.
Tor was always a government tool.
Ulbricht wasn't caught because of flaws in Tor, but he made other mistakes. He posted stuff on LinkedIn alluding to his activities, he used a real photo on his fake IDs to rent servers, he used his real name, posting a question on stack over flow about running a Tor service, he posted his personal gmail, looked for couriers on Google+, and lastly paid an undercover cop for a hit.
As for getting his location, once the feds gained acccess to silk road, they matched up activity logs, his posting habits were consistent with being in the pacific time zone, and they matched up his user name between his posts on silk road as altoid and he reused the same screenname, associated with his gmail address and full name, on other websites.
A series of stupid opsec mistakes got him caught, not Tor.
Unless, of course, they want everybody, which even they don't have the resources to handle.
When did he sell drugs?
He facilitated drug sales. If you setup ‘clucks brick and mortar Silk Road’ you’d be just as guilty.
I don’t think that was ever rosses ethical objective though, I’m pretty sure he felt that drugs should be less illegal and safe. I’m under the impression that Silk Road had rules on what could be sold, and that post SR markets do allow those things, but I could be wrong.
Not defending him, but clarifying that it's not proven "he directly did that"
In a world where Tor is not a honeypot of some three letter agency, there are implementations of projects like Jim Bell's Assassination Politics. In a world where Tor is not a honeypot its use would be banned, much like the use of Tornado Cash was banned and shut down until the secret services took control of it.
And we obviously don't live in such world.
There are many places in the world where direct access to Tor is blocked. There are many countries where use of a VPN is illegal, VPNs are required to log by law, etc. I disagree with this premise.
There are generally two types of countries, those that seek agency, independence, and freedom of rational thought and action; which requires privacy, and there are those that seek ultimate control, imposing dependence, coercion and corruption of reason; from the top down.
The cultures that seek total control generally fall under totalism and are parasitic in nature. The ones that seek agency, freedom, and independence, Protean.
"VPN services may soon become a new target of EU lawmakers after being deemed a "key challenge"" https://www.techradar.com/vpn/vpn-privacy-security/vpn-servi...
Many comments talk about exit nodes for surveillance, but there is a totally different vector of use and considerations that dint apply when you aren't trying to access clearnet
And even on darknet it depends on what you’re doing
Reading the NY Times’ darknet site or forum or even nuet browsing darknet markerplace from Tor Browser, whereas I would use a Tor OS like Tails or dual gated VM like Whonix for doing something illicit