Topic: Wall Observer BTC/USD - Bitcoin price movement tracking & discussion - page 29702. (Read 26710230 times)

Watch them scooping the cheap coins. IF gox ever allows btc withdrawals, all asks will be pulled, and they will flash "crash" to $1000.

Has anyone even tried doing a withdrawal with stamp or BTC-e?

bitstamp is OPEN - WITHDRAWAL just hit blockchain!

Why havent gox prices begun recovery if its true withdrawals are coming back???

insider trading now on gox? pushing the price up

Why havent gox prices begun recovery if its true withdrawals are coming back???

Its coming soon, just like a swift transfer from Tibanne co ltd.
We all know how deceitful Gox is..

Why havent gox prices begun recovery if its true withdrawals are coming back???

Why havent gox prices begun recovery if its true withdrawals are coming back???

Real trolls don't trade and don't own any bitcoins.

I will stop trolling when Bitcoin hits 200-300$ , promised.

So Fonzie, did you hit your short targets or are we subject to another bout of your uber-trolling?

Its going sideways, again 

So Fonzie, did you hit your short targets or are we subject to another bout of your uber-trolling?

Its going sideways, again 

Let's se if understood correctly.  The "malelability" of transaction requests can cause two problems:

  * First, old or custom wallet software may broadcast out "non-canonical" transaction requests (like writing "$020,0" on
    check instead of "$20,00").

    Such requests were originally accepted by the bitcoin network, but  a few months ago the protocol was tightened
    and they started being rejected.

    An exchange that issued such a request in order to execute bitcoin withdrawals by clients had to either re-issue the transaction
    request, or cancel the withdrawal and credit back those bitcoins to the client's account.  If the exchange did either of these
    two things, the result would be only annoyance to clients as their withdrawals were delayed or failed.
   
    If the exchange did not do either of those things, the bitcoins would be subtracted from the client's account but would remain
    in the exchange's own wallet.  If the exchange also failed do proper accounting (which it probably did, or else it would have detected the
    problem), it may have believed that the apparent BTC surplus  (bitcoins in its own wallet minus sum of all bitcoins in the clients accounts)
    was its profit from fees; and therefore converted that surplus into dollars to pay for expenses and dividends.  In extreme situations,
    the exchange may become insolvent (unable to produce enough bitcoins and dollars to honor all its client's accounts.)

  * Second, some hackers exploited the malleability to steal coins from any exchange that issued non-canonical requests.
   
    The hacker would open an account at the exchange, put some bitcoins there, and request a withdrawal. He would then watch
    for the corresponding transaction request as it was broadcast by the exchange, and would broadcast a mutated copy (like
    changing "$020" to "$20").  The network would execute the "canonical" version and reject the original for being non-canonical (and
    also an attempted double spend). 

    The exchange would then think that the transaction had failed, and therefore would either re-try it, or cancel the withdrawal and
    credit back the coins to the hacker's account.  In the first case the hacker would get the withdrawal executed two or more times
    but debited only once; in the second case he would get the withdrawal executed without his account being debited.  Repeat
    to taste.

    Again, this hack could be spotted imediately if the exchange kept proper accounting, as it would notice that the coins
    were taken out from its own wallet in spite of the transaction being apparently rejected.

Is this understanding correct?

If so, does anyone know whch exchanges had which of these problems, and how many bitcoins  they overspent or had stolen?

It seems that for MtGOX the amount involved is at least 50,000 BTC or more, and one of those two problems had been occurring for several months.  How could they fail to notice and diagnose such a big problem?