Attempt to compress the information from https://www.ctrl.blog/entry/tribler-onion-routed-bittorrent.html

1 - Paragraph 10 : "However, a large-scale monitoring effort of the internet — hello, NSA! — could still correlate the timing of unencrypted traffic going into an exit node with the obscured traffic it routes into the Tribler onion network" (this is sort of an unsolvable issue but I'm not entirely sure how practical of a threat vector it is/would-be as it seems like there are enough background communications that could 'drown out' this sort of packet tracing)

2 - Paragraph 10 : "Yet, it takes only a single click in Tribler’s settings dialog for your computer to become an exit relay too! Yikes." (not sure how much of an issue this is practically speaking)

3 - Paragraph 11 : "The exit relays are also considered to be regular relays. By default, Tribler is configured to only use a single relay. Your one and only relay node, as per the default configuration, is also the exit relay."(the Tribler website is fairly open about the multi-mode onion routing and presumably anyone who needs stricter security would ensure they have it, but there are later points made that do give this a bit more relevance)
3.1 - Paragraph 13 : "Every user is a relay by default, and there’s no [easy] way to opt-out of it. Your client will only ever acting as an intermediary relay that relays end-to-end encrypted connections (unless you opt to be an exit relay). Yet, there’s little demand for other relays as the default configuration only uses the exit relays."
3.2 - Paragraph 14 : "I’m uncertain why the project promotes its onion routing capabilities, but don’t take advantage of them by default."
3.3 - Paragraph 15 : "The tyranny of the default means most users will use Tribler, and practically be at the mercy of the exit nodes not to monitor their activities. It’s not entirely clear to me why the more anonymous three-relay setting isn’t the default configuration."
3.4 - related to 6
3.5 - related to 9

4 - Paragraph 16 : "The Tribler project’s test suites don’t proactively try to detect unexpected network connections or other information leaks. ... The test suite could be more proactive by including a mock Domain Name System (DNS) server and a review of which domain names the client tries to contact. Similarly, it could log connections to look for unexpected or unencrypted traffic, e.g. unencrypted DHT lookups or connections to web servers. There have been several examples of DNS leaks and unencrypted connections leaking out of Tribler." (the following paragraphs go over a few examples that have been addressed)

5 - Paragarph 21 : "Tribler doesn’t support the webseed BitTorrent protocol extension (BEP 19) despite having limited support for TCP/HTTP tunneling. ... This feature is important for ensuring that unpopular and newly released torrents work. The Humble Bundle store, for example, distributes its downloads through webseed-backed torrent files."

6 - Paragraph 22 : "There’s an elephant in the room, and it’s time to address it: Tribler’s bandwidth token system. " (there is a lot of additional detail here so I'd highly suggest referencing the original post regarding this point)
6.1 - related to 7
6.2 - related to 9
6.3 - Paragraph 30 : "You need to share three times as much data as you download when using Tribler to pay all the relays. The problem is that no one wants to download from a Tribler client. You don’t earn any tokens for uploading through exit relays to other BitTorrent clients. You even lose some credits on the protocol overhead that’s relayed through other Tribler users. A known problem Tribler developers refer to as “token blackholing.” " (to be honest not sure how to best classify this)
6.4 - Paragraph 31 : "Tribler knows it has an undersupply of exit nodes, yet not even other Tribler users will download from your Tribler instance. The most common solution to a network routing problem is to select the shortest route. Tribler also prefers the shortest relay route as it can be assumed to be faster. Therefore, Tribler prefers downloading through an exit relay as it’s both faster and cheaper than downloading from other Tribler users over multiple relays. Tribler could help mitigate this problem by making the client prefer transferring internally in its relaying network despite the higher “token cost.” " (again, not sure the best way to classify this so I'm just bolting it onto 6)

7 - Paragraph 25 : "The only source of new bandwidth tokens is the 20 GB granted to new users. The network depends on ‘mining’ an unending stream of new clients who’re willing to join the network before their clients eventually slow down and they stop using it."
7.1 - Paragraph 25 : "It’s much faster and easier to reset your Tribler instance to get another 20 GB worth of tokens than it is to earn them legitimately by relaying traffic in the network."
7.2 - Paragraph 25 : "Your token balance decreases faster over time due to the token cost for protocol upkeep than you earn tokens for relaying traffic for other users."
7.3 - related to 9

8 - Paragraph 26 : "The token balances are a cryptographic blockchain signed by the other participants you communicate with in the network. The blockchain records the amount of data transferred, a cryptographic hash representing the participants, and the time of the transfers. It doesn’t record what was transferred. However unimportant metadata like this may appear, there have been countless examples of someone managing to stitch together data like this with other data to glean more information than what is apparently there" (no examples are given of how this data could be aggregated to cause issues and to be honest I'm not 100% convinced that they could be - this feels like a critique which very much necessitates a proof-by-example)

9 - Paragraph 27 : "A possible fix would be to increase the default number of relays to three. As discussed, this would make anonymity stronger, and also help circulate bandwidth tokens to more peers throughout the network. It wouldn’t fix the imbalance of exit nodes accumulating ever more bandwidth tokens, however."

10 - Paragraph 29 : "You can find similar thoughts on rewarding users for sharing rarer files in the Tribler mission statement, but it has yet to materialize in the client. You currently lose credits due to the cost of paying for the protocol overhead by seeding unpopular torrents."

11 - Paragraph 32 : "This brings us back to the topic of the exit relays. ... The exit relays can also conceivably manipulate what you’re downloading."

12 - Paragraph 33 : "The exit relays are perfectly positioned to carry out a monster-in-the-middle (MITM) attack against your BitTorrent transactions." (I'm not confident enough I could trim down the following points due to my lack of familiarity in this area so I'd heavily suggest referencing the original post to explain this one)
12.1 - Paragraph 34 : "Unfortunately, the SHA-1 algorithm has been known to be weak and spoofable since 2004. It’s now considered achievable to construct a file (potentially with a deanonymizing or otherwise malicious payload) with the same SHA-1 has as a target file."
12.2 - related to 13

13 - Paragraph 36 : "This problem isn’t unique to Tribler and affects all BitTorrent clients. However, Tribler is uniquely susceptible to it because of its reliance on unknown intermediaries. The BitTorrent protocol version 2 addresses this vulnerability by upgrading the hashing algorithm used for the BTIH to SHA-256. Tribler doesn’t yet support version 2 of the protocol despite being more at risk than typical BitTorrent clients."

14 - Paragraph 36 : "Tribler offers improved anonymity when downloading torrents. However, it also comes with built-in features for searching for and discovering new torrents. These features do not provide any anonymity. The infrastructure for encrypting and relaying queries is there in the client, but it’s not used for these purposes"
14.1 - Paragraph 37 : "Searches are sent from your client to other Tribler users in cleartext. Likewise, your client may receive and respond to other users’ queries in cleartext. Anyone monitoring your network can see what you search for and what search results are returned to you. They cannot, however, see what — if anything — you choose to download. They can infer that any large data transfer starting immediately following a search query is for one of the returned results."

15 - Paragraph 38 : "Search queries are by default filtered against an optional family-friendly filter. The filter discriminates against some ethnicities, hair colors, and sexual identities. " - addressed in #6259

16 - Paragraph 39 : "Tribler also has a system for content discovery and creator channels. Neither creating a new channel and sharing content, nor subscribing to an existing channel is anonymous"
16.1 - Paragraph 39 : "Tribler doesn’t communicate that search and its other discovery methods aren’t anonymized."
16.2 - Paragraph 40 : "This comment shows the stark contrast between user expectations of privacy versus the project’s own wants and goals. The Tribler client never communicates this to the user. No one expects that some parts of a privacy-focused software project won’t feature the same privacy-preserving technologies as the core software. These features need to be made private, or otherwise come with large obnoxious privacy warnings."
16.3 - Paragraph 43 : "It’s also unsuitable for dissidents or other groups looking for more private and secluded places to share on the web. The lack of anonymity makes it wholly unsuited for those groups. "

17 - Paragraph 42 : "Tribler channels are unappealing to potential creators looking to distribute their works. They’re difficult to manage; and it’s unclear how you back it up, move it between devices, or even share your channel with others. There is, for example, no way to get a link to it or any other sharable identifier for use on social media."
17.1 - Paragraph 43 : "It’s also unsuitable for dissidents or other groups looking for more private and secluded places to share on the web. The lack of anonymity makes it wholly unsuited for those groups. "
17.2 - Paragraph 44 : "The network overhead of maintaining the search index and updating channels is deducted from your token balance and paid out to other peers. This is why you can experience that the token balance is gradually decreasing over time even when you’re not downloading anything."
17.3 - Paragraph 45 : "In my experiments, disabling the search and channels features significantly accelerates how fast your tokens vanish from your balance even when you let the client sit idle. In theory, the token balance should then only ever increase as you only participate by relaying traffic. However, I’m seeing the opposite and the token balance goes down almost twice as fast."
17.4 : Paragraph 46 : "There are no options for disabling these features in the settings screen, but they can be disabled through the configuration file."

Edit Report
Pub: 11 May 2024 12:27 UTC
Edit: 11 May 2024 12:28 UTC
Views: 36