Mycryptomixer.com small amount scam

[mantari]

What happened: 
I've sent two transactions of 0.0016 BTC to mycryptomixer.com to one mixing address. Both transactions showed up under my order, but both as "too low amount". The website shows the minimum processing amount is 0.0030 BTC, nowhere it says it should be only 1 transaction. I've sent in total 0.0032 BTC. The owner does not want to process this order and ignores all further contact.
Scammers Profile Link: https://bitcointalk.org/index.php?action=profile;u=2734674
Reference Link: https://mycryptomixer.com/
Amount Scammed: 0.0032 BTC
Payment Method: Bitcoins
Proof of Payment: https://www.blockchain.com/btc/address/37Gjp2ak2K8McCZJu13vGhR23eup4GVJLk
PM/Chat Logs:
Hi,

As I received no reply anymore I asume you don’t want to fix this transaction issue.
Let’s continue this conversation on bitcointalk tomorrow. I’ve sent 2 transactions with a total of 0,0032 BTC, which is above minimum. I have screenshots and the LoA.
Other users should be warned, this is small money scam. If this happens with small amounts, big amounts also can’t be safe.

Regards

> 27 feb. 2021 21:45 <removed>:
>
> Hello,
>
> Don’t worry about the blockchains fees, I will cover these costs.
> I’ve sent BTC 00,32 which is more as the minimum. It’s not written on your site it should be 1 transaction.
> I see two options: 1 combine both transactions to the final destination or 2 refund and lower the ammount with the fee.
>
> I don’t see any problem in above options. This is technically possible. If not it seems like scamming of small amounts to me.
>
> Best regards
>
>> 25 feb. 2021 19:50 MyCryptoMixer <MyCryptoMixer@protonmail.com>:
>>
>> Hello,
>> Unfortunately we do not provide refunds for too low orders because of high blockchain fees and transaction privacy.
>> The minimum amount is clearly listed above the deposit address.
>>
>> ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
>>>> Wednesday, February 24, 2021 12:55 PM, <removed>:
>>>
>>> Dear,
>>>
>>> I have two transactions under order 7vhr2r-p641mb-pzu23x which are not going through.
>>> Can you please combine both transactions and complete the order?
>>> Attached is the signed message.
>>>
>>> Regards
Additional Notes:
Just wanted to say if the owner does not fix this: ignore this mixer if you're dealing with small amounts, you will lose your money. If he's scamming small amounts, I would definitely not trust him with bigger amounts. Asking for help will not help as the owner will ignore you.

[1714175597]

1714175597

[1714175597]

1714175597

[1714175597]

1714175597

[acosimo]

Next time send 100 transactions 0.00003 BTC each and come back here to complain.

[LoyceV]

Both transactions showed up under my order, but both as "too low amount". The website shows the minimum processing amount is 0.0030 BTC, nowhere it says it should be only 1 transaction.

This is incorrect, it does show each transaction must exceed the minimum:

However, I do agree this isn't clear. This should have been mentioned right under "Transfer between 0.0030 BTC.....". Now there's a CALCULATOR button in between, and when I click it, I get this:

If their own calculator doesn't even account for their own minimum, it clearly looks as if it's designed as a trap to keep any deposits under 0.003 BTC (worth $185 by now!).
A mixer's calculator should be absolutely accurate!

>> Unfortunately we do not provide refunds for too low orders because of high blockchain fees and transaction privacy.

Interesting how that didn't stop them from using the amounts to send to another address.
Even more interesting: all inputs to those 2 transactions are lower than 0.003 BTC:

37eLAbP3GmW8ncJ4uEKkVNTct6tuKCB6nb 0.00159178 BTC
37Gjp2ak2K8McCZJu13vGhR23eup4GVJLk 0.00166454 BTC

37Gjp2ak2K8McCZJu13vGhR23eup4GVJLk 0.00167152 BTC
3GmXAmPYDL9zg1S3VG6xd2JCuQFLw5bL4S 0.00228557 BTC
37eLAbP3GmW8ncJ4uEKkVNTct6tuKCB6nb 0.00273758 BTC

Are these all deposits that didn't meet the minimum? Note that there's another address with 2 inputs, I guess that's another user who to sent a second deposit in order to reach the minimum of 0.003 BTC.

@mantari: you should leave MyCryptoMixer appropriate feedback and you could consider creating a Flag against them. If you do, add the link to the Flag to your post to ask for Support.
I'd say the CALCULATOR might justify a written contract violation Flag, but the fact that the site gives opposing information deserves at least a Newbie warning Flag.

[MyCryptoMixer]

A minimum deposit has not been reached, the transaction has not been processed. Those are the rules of mixing which have not been followed and haven't changed since the inception of our service.

I have acknowledged the incident and made effort towards making sure this does not happen often. As LoyceV noticed, there is a note in Incoming Transactions table. I agree it may not be in the best spot, I am not a designer. For what I know though, putting it next to other already ignored information, the minimum deposit, is unlikely be a better choice. The current spot was selected as it is very close to the place where user finds out their transaction is too low. The goal is to prevent them from sending more money.

In response to the comments, I decided to duplicate the note next to the address field and color the old one red when small transaction arrives. I hope this gets the attention. The calculator have also been updated to note minimum deposit, because the red outline (visible on LoyceV screen) apparently was not enough - to the point of accusing MCM of deliberately designing it to scam people.

Interesting how that didn't stop them from using the amounts to send to another address.

Yes, it is inconvenient to process such order, but this does not mean we should throw the money away. There are multiple issues with processing small transactions - the one I care about the most is exposing MCM addresses, a huge security risk.

If there were no limit, it would be trivial to expose multiple MCM addresses with many small transactions. Worst case, the attacker could scan entire MCM wallet. This is why we do not accept small deposits and if we receive one, such transactions are only combined with other almost depleted addresses whenever possible.

MCM has a lot of internal addresses with less than 0.003 BTC. Those are mostly created by people mixing close to the minimum amount. Consider two mixes of 0.005 BTC and 0.003 BTC - we are left with 0.002 BTC lying on the change address.

A much better solution would be to charge a minimum amount (say 0.00025 BTC) for each incoming deposit to cover consolidation fees, and just get rid of the 0.003 BTC minimum entirely.

Continuing on the point above, we want to avoid small transactions as much as possible. Taxing the customers because a small group fails to follow the rules is not something I consider.

[mantari]

@LoyceV: interesting is the line “Transactions do not sum up” in your screenshot.
I’m pretty sure this text was not there under my incoming transactions at that time. I checked the page about 10 times why my transactions didn’t go through. I wouldn’t be so dumb to send another transaction if this line was there.
@MyCryptoMixer: seems this text was added after our short discussion. I understand your security concerns and other points, but hey, I’m no test bunny spending my money to make your site fool proof. A refund would be fair in this case, this MCM address is already exposed anyway.

[bL4nkcode]

@MyCryptoMixer: [...] A refund would be fair in this case, this MCM address is already exposed anyway.

You would be lucky if they will refund you considering you transfer below their minimum, and some mixers considers it as donation.

[suchmoon]

@LoyceV: interesting is the line “Transactions do not sum up” in your screenshot.
I’m pretty sure this text was not there under my incoming transactions at that time. I checked the page about 10 times why my transactions didn’t go through. I wouldn’t be so dumb to send another transaction if this line was there.

Yeah I'm quite certain it wasn't there. I checked the site after you created this thread and didn't see that disclaimer. Now it's been moved above the calculator so they're clearly tweaking it as they're reading this thread. Sketchy AF. They should refund you, pay the TX fees out of pocket, and apologize profusely.

Continuing on the point above, we want to avoid small transactions as much as possible. Taxing the customers because a small group fails to follow the rules is not something I consider.

Failing to disclose the rules properly is a much bigger problem, so start by refunding the customer.

Edit: even though I didn't take a screenshot here is one from your own medium article. I think it's extremely dishonest to claim this then:

As LoyceV noticed, there is a note in Incoming Transactions table.

[MyCryptoMixer]

Now it's been moved above the calculator so they're clearly tweaking it as they're reading this thread. Sketchy AF.

You wrote this an hour after my post above, in which I explained how the text was moved according to LoyceV suggestion. You even quoted the post...? The note was added a while back because of a few incidents involving people failing to comply with the minimum deposit and BTC price spiking really high. It was not there a year ago when the article was published.

They should refund you, pay the TX fees out of pocket, and apologize profusely.

At this point it is getting quite frustrating how people whose posts are paid for by the competition keep telling me how to run the service. Throwing dirt left and right without a single valid proof nor even reason.

The visuals of MCM have been updated to reflect the constructive feedback received. If your input can be brought down to "sketchy AF... Edit: Oh, I did not notice... Still sketchy [proof based on a year old article]", please refrain from posting. To be clear, the same goes for anyone defending MCM.

Seems this text was added after our short discussion. A refund would be fair in this case, this MCM address is already exposed anyway.

You are right. I got too involved with LoyceV post and did not read the dates carefully. I was not expecting such post so long after the incident. I was considering adding such note after the price of BTC nearly quadrupled in a single month - making 0.003 BTC worth significantly more.

There are other reasons past address exposure for not issuing the refund - it takes my effort to fix your mistake; any interaction with the wallet puts not only 0.003 BTC but all XX BTC at risk - but in this one instance I am willing to award you a *bug bounty* as you ultimately helped the site to get better. Please send me an email with an address you want the 0.0032 BTC to be transferred to.

@LoyceV, @suchmoon
Please do a little more research before posting your conclusions. The fact you accuse MCM of deliberately stealing $90 (at the time, only because BTC price just spiked) is a bit embarrassing...

[suchmoon]

@LoyceV, @suchmoon
Please do a little more research before posting your conclusions. The fact you accuse MCM of deliberately stealing $90 (at the time, only because BTC price just spiked) is a bit embarrassing...

Cut the drama shit. I didn't accuse you of stealing. Your opaque rules are the problem. As of this post there is still no mention of this minimum TX requirement in your FAQ, which seems to also moonlight as your TOS. Even the note that you added doesn't say that you'll confiscate deposits smaller than the minimum. If you take user's money (however it is called, donation, fee, etc) it should be very clearly and explicitly stated.

If you want to be deliberately obtuse and pretend that this is just competition-paid posts, feel free to put me on ignore.

[mantari]

@MyCryptoMixer: I've just mailed you, thanks for understanding. I'm not crying for loosing a few bucks if it was my mistake, my point was the rules are not clear. In this case this rule was not visible at all at your site. If hundreds of people make this mistake, it's easy money for you..
Anyway, I'll leave you positive feedback once the refunds received.

[LoyceV]

The calculator have also been updated to note minimum deposit, because the red outline (visible on LoyceV screen) apparently was not enough

I didn't guess any meaning for the red border in my screenshot. Your current update (showing the minimum amount in red font when a low value is entered into the Calculator) is an improvement, but the Calculator still shows the user will receive an amount when he sends 0.0016. The Calculator should show 0 as receiving amount in this case.

There are multiple issues with processing small transactions - the one I care about the most is exposing MCM addresses, a huge security risk.
If there were no limit, it would be trivial to expose multiple MCM addresses with many small transactions. Worst case, the attacker could scan entire MCM wallet. This is why we do not accept small deposits and if we receive one, such transactions are only combined with other almost depleted addresses whenever possible.

What the difference with processing small transactions, and only using other small inputs to send them? That mitigates this attack vector on your wallet.

MCM has a lot of internal addresses with less than 0.003 BTC. Those are mostly created by people mixing close to the minimum amount. Consider two mixes of 0.005 BTC and 0.003 BTC - we are left with 0.002 BTC lying on the change address.

This sounds perfect to use as an input for OP's transaction! What you consider a problem could be the solution to get rid of small amounts.

Continuing on the point above, we want to avoid small transactions as much as possible. Taxing the customers because a small group fails to follow the rules is not something I consider.

Fair point. An easy solution would be to only set a 0.00025 BTC deposit fee for deposits under 0.003 BTC.

At this point it is getting quite frustrating how people whose posts are paid for by the competition keep telling me how to run the service.

Well, you're the one who ignored your customer:

As I received no reply anymore I asume you don’t want to fix this transaction issue.

Throwing dirt left and right without a single valid proof nor even reason.

I've posted enough reason. You just don't like it.

There are other reasons past address exposure for not issuing the refund - it takes my effort to fix your mistake

That's ironic, it took my effort too, and it's not even my business!

any interaction with the wallet puts not only 0.003 BTC but all XX BTC at risk - but in this one instance I am willing to award you a *bug bounty* as you ultimately helped the site to get better. Please send me an email with an address you want the 0.0032 BTC to be transferred to.

If you don't want to touch your server's wallet, use a different wallet to refund customers.

I appreciate resolving this case.

@LoyceV, @suchmoon
Please do a little more research before posting your conclusions. The fact you accuse MCM of deliberately stealing $90 (at the time, only because BTC price just spiked) is a bit embarrassing...

Based on your Calculator, you're the one who should be embarrassed:

[mantari]

Just letting you know I received a refund from MyCryptoMixer!