Topic: How to stop 'double spend' attack - page 2. (Read 3761 times)
8. How can I (if at all) defend myself from someone performing a double spend attack when sending me coins? (like the OP topic states)
I looked at some of the transactions, but did not see any issues with double spending, even when you were still experiencing the problem yesterday. I admit I did not look through them all or maybe I missed something.
Other people clearly stated they could also see some of the double spend warnings - I wasn't seeing things - so maybe you did miss it.
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That blockchain.info warning shown on an address (it doesn't appear on transactions) can happen when unconfirmed coins are spent and blockchain.info thinks they may never be confirmed.
Most of the transaction ids I posted had already been confirmed, some in their hundreds. How can the block chain think a txn with hundreds of confs might never be confirmed?
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The warning went away because the transaction(s) in question received a confirmation. (If I am wrong about the blockchain.info's warnings, please let me know.)
As above, the txn(s) in question were already solidly confirmed. So why was the warning there in the first place for a well aged txn?
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The only difference in the two wallet screenshots is one (https://i.imgur.com/TdZfNG1.png) is missing transactions that the other (https://i.imgur.com/fyQCrWR.png) has listed. It seems the wallet fixed itself after the corrupted data issue was resolved and it was fully synced.
I restored the wallet from a backup and resynced the last weeks worth of txns - it didn't take long to fully sync - yet hours and hours later the updown (and only the updown) txns were showing n/a for address and txn id. And these were the addresses showing the double spend warnings.
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What questions do you still have?
1) Can a set of transactions to a specified btc address be reversed?
2) If so, how is that done?
3) If so, who does it? - and under what circumstances?
4) If so, how secure is the process? Is it susceptible to a malicious actor?
5) What is the trigger for blockchain.info to show this double spend warning for an address?
6) Can I be sure (even after hundreds of confs) that a payment I recieve has really been recieved?
7) Would you be so nonchalant if you were watching txns disappear from your own wallet?
Well I also thought it was not possible to unconfirm a transaction that had hundreds of confirmations - but it must be possible. Isn't that what they did when the blocked chain forked last year - they rolled back to a point in time and all txns up to that point were lost.
That is why I used the word selected. It is not possible for one specific transaction in a block to become unconfirmed while the rest in the same block are unaffected.As previously stated - I no longer have any issues with any txns. I did have an issue yesterday and I posted a large pile of txn ids if you actually want to read the thread.
I looked at some of the transactions, but did not see any issues with double spending, even when you were still experiencing the problem yesterday. I admit I did not look through them all or maybe I missed something.Also as previously stated - the fact that you state the warnings I was seeing regarding the missing updown txns does not necessarily mean anything is far from satisfying. They could mean something and you stating that they might not doesn't add anything. Unless you actually knew what they meant. Which you dont.
That blockchain.info warning shown on an address (it doesn't appear on transactions) can happen when unconfirmed coins are spent and blockchain.info thinks they may never be confirmed. The warning went away because the transaction(s) in question received a confirmation. (If I am wrong about the blockchain.info's warnings, please let me know.)The only difference in the two wallet screenshots is one (https://i.imgur.com/TdZfNG1.png) is missing transactions that the other (https://i.imgur.com/fyQCrWR.png) has listed. It seems the wallet fixed itself after the corrupted data issue was resolved and it was fully synced.
So all of my questions remain unanswered.
What questions do you still have? Nah I'm not willing to believe that - it was only the updown txns that were affected - if was a problem with my own wallet then why with only updown? Also I only saw the double spend warning with txns associated with updown. You explanation is far from satisfying.
It is not possible for select transactions, with many confirmations, to suddenly become unconfirmed in the blockchain and then disappear from your wallet. There is no way to "suspend" the transactions like you have suggested before. They either are confirmed or unconfirmed. Do you have an issue with a specific transaction? If so, what is the transaction id (not the address) and what problem do you think exists?
Also, as I previously stated, that warning you may see on blockchain.info doesn't necessarily mean anything.
Well I also thought it was not possible to unconfirm a transaction that had hundreds of confirmations - but it must be possible. Isn't that what they did when the blocked chain forked last year - they rolled back to a point in time and all txns up to that point were lost.
As previously stated - I no longer have any issues with any txns. I did have an issue yesterday and I posted a large pile of txn ids if you actually want to read the thread.
Also as previously stated - the fact that you state the warnings I was seeing regarding the missing updown txns does not necessarily mean anything is far from satisfying. They could mean something and you stating that they might not doesn't add anything. Unless you actually knew what they meant. Which you dont.
So all of my questions remain unanswered.
[edit] see for yourself here
http://nottm28.imgur.com/all/
Nah I'm not willing to believe that - it was only the updown txns that were affected - if was a problem with my own wallet then why with only updown? Also I only saw the double spend warning with txns associated with updown. You explanation is far from satisfying.
It is not possible for select transactions, with many confirmations, to suddenly become unconfirmed in the blockchain and then disappear from your wallet. There is no way to "suspend" the transactions like you have suggested before. They either are confirmed or unconfirmed. Do you have an issue with a specific transaction? If so, what is the transaction id (not the address) and what problem do you think exists?
Also, as I previously stated, that warning you may see on blockchain.info doesn't necessarily mean anything.
When I checked this morning the missing txns were back - http://nottm28.imgur.com/all/
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
So the reason for the anomaly is still a mystery or it has been discovered ?
Nah I'm not willing to believe that - it was only the updown txns that were affected - if was a problem with my own wallet then why with only updown? Also I only saw the double spend warning with txns associated with updown. You explanation is far from satisfying.
When I checked this morning the missing txns were back - http://nottm28.imgur.com/all/
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
So the reason for the anomaly is still a mystery or it has been discovered ?
Bitcoin crash ? so is this the right moment for change myself and all my Bitcoins to FIAT ? 
When I checked this morning the missing txns were back - http://nottm28.imgur.com/all/
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
So the reason for the anomaly is still a mystery or it has been discovered ?
When I checked this morning the missing txns were back - http://nottm28.imgur.com/all/
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
I think someone noticed a double spend attack from updown and somehow suspended all txns from the last 2 weeks. Now they have been released.
This is some scary shit...
The album is missing. Please reload it. I would like to research this myself. This fits into a Ghash.Io casino attack senario I'm researching.
they work for me, here are they
Thanks
FYI, also check out updown's post in the updown thread on July 1. It says their wallet was cleaned out recently due to double spend attack. Wow. Maybe they are trying to get back at people who stole money from them with double spending?
Yeah, so who are making this vicious attacks? and how are they making them?
FYI, also check out updown's post in the updown thread on July 1. It says their wallet was cleaned out recently due to double spend attack. Wow. Maybe they are trying to get back at people who stole money from them with double spending?
Not saying whether OP has a legit complaint, however I would point out that it appears that the updown sig campaign is a total scam.
legendary
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Reverse engineer from time to time
Post the txid of the transactions that you claim are problematic.
The album is missing. Please reload it. I would like to research this myself. This fits into a Ghash.Io casino attack senario I'm researching.
they work for me, here are they
The album is missing. Please reload it. I would like to research this myself. This fits into a Ghash.Io casino attack senario I'm researching.
This is quite concerning if you can receive a double spend with over 100 confirmations. How??
Lol so we need some forensic investigation in here, but why are not more users of updown complaining about it?? or is because they havent spend the amount received? 
In that case he could have gone over localbitcoins and sold thousands of dollars of btc worth or sell bitcoins even at cash in person.
In that case he could have gone over localbitcoins and sold thousands of dollars of btc worth or sell bitcoins even at cash in person.
Would be interested to see if any other 'winners' can spend those coins...
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