Dash De-anonymization ContestIcebreaker and other trolleros:
I have donated $1 to Monero's development team. I sent 0.25 Dash (TX ID: 59d51690d4b56ddbf1e393fa8d3a49bcfc3247f270f36be3b6ee411802666cba-000) to shapeshift.io, which converted it to Bitcoin and sent it to the official Monero donation address listed at
https://getmonero.org/getting-started/donate/.
I challenge you to de-anonymize this transaction. To make it just a little easier, I only used four rounds of Darksend, so it's exponentially less private than it would be with the maximum eight rounds.
Please tell me what address this transaction originated from.
Cheers!
Analysis of the Dash de-anonymization contest transaction:
https://www.dash.org/forum/threads/evaluating-the-privacy-of-privatesend.32472/#post-187480Here is the the result for 59d51690d4b56ddbf1e393fa8d3a49bcfc3247f270f36be3b6ee411802666cba with 4 rounds assumed:
https://pastebin.com/zv2v8NhBFor example 911d8271516aab449dd108b002fe82e3757c2bf181040ee7718f088c871c96da=0.25711422641816556 means that 911d8271516aab449dd108b002fe82e3757c2bf181040ee7718f088c871c96da appeared in 25.71% of the one million randomly generated combinations.
This bar chart shows the daily percentage of mixing transactions where are inputs are from the same transaction:
This bar chart shows the daily average branching factor of mixing transactions (number of different transaction ids in the inputs):
What is important here is that immediately after November 8th 2017 the percentage of mixing transactions where all inputs are from the same transaction has increased significantly. The average branching factor has also decreased significantly. This data suggests that the PrivateSend "improvements" released in 0.12.2 on November 8th has actually caused mixing to become significantly less efficient (less privacy achieved per mixing round).
If the branching factor was always 1 then there would be exactly the same number of create denominations transactions reachable from a PrivateSend transaction as the PS transaction has inputs. When the branching factor is higher then there should at least on average be more create denominations transactions reachable from a PS transaction.
Here is the daily average number of create denominations transactions reachable from a PrivateSend input transaction within 2-3 rounds of mixing. The x-axis date represents the date when the PrivateSend input transaction was included in a block.
As you can see the number dropped significantly after November 8th indicating that the average anonymity set is smaller. This should certainly make statistical analysis a lot more effective meaning that there is less privacy.
"If private-send anonymity is broken the value of dash will plummet" - Bitedge, Masternode owner, Aug 13, 2017The long-delayed Dash 12.3 is being held back (among other reasons) because of the sudden revelation of a gaping hole in PrivateSend's privacy. Dash Core Group is scrambling to fix this, but they only started QA and other testing less than a week ago (
https://github.com/dash-docs/dash-docs/commit/cbfaf63cbaf3b2fc68ec0ac5d09cbf5f937bdc59).
Maybe you guys should have voted for
https://www.dashcentral.org/p/PrivateSend-De-Anonymization-Contest when you had the chance 8 months ago, instead of funding Shrem Attacks, RVs, and do-nothing PR firms?