Post
Topic
Board Development & Technical Discussion
Merits 6 from 3 users
Re: Breaking Mixing Services
by
mocacinno
on 07/03/2019, 09:07:14 UTC
⭐ Merited by Welsh (3) ,ETFbitcoin (2) ,hugeblack (1)
Interesting reading material... I've quickly browsed trough your attack on coinmixer.se, and my first reaction was that you were able to attack them because they did not include any variation in the creation of their output transactions. I mean, if a mixer only creates output transactions with version = 2, sequence = 294967294, locktime > 0 and the fee is within a very small range, it should become pretty easy to identify those transactions (and you did).

Don't get me wrong, what you did was a very nice thing... I personally wouldn't have the patience to analyse a mixer's method like you did, and i personally feel that you discovered a huge security flaw in coinmixer.se's mode of operation... However, i can hardly imagine it being impossible to fix these issues...
They basically had to generate more "random" output transactions, making sure there isn't a clear pattern in them... If they'd do this, it looks to me like an attack on their service would have been much harder.

That being said: i quickly browsed trough your thesis, so i haven't read your exact conclusions (yet), but i really think you did a great job... Raising awareness about security flaws that have been made even by the biggest mixing services is a good thing for the community Smiley