I’m sure there are many of you wondering just how many platforms out there were affected by the malleability issue reported to have greatly affected a major exchange (I won’t name names - but you know who they are)
I can assure you that we were NOT affected and here is why:
When a malleable transaction occurs (Which I’ve mainly only seen on BitCoin, but I think there may have been a couple in DogeCoin as well), our system automatically detects the new withdrawal transaction in the wallet, finds the original transaction, and updates with the new transaction id accordingly. In a worst case scenario, if the original transaction cannot be found by the system, it results in two withdrawals on a users account when in fact only one occurred. This is rare and is corrected by manual intervention.
When a user reports they did not receive a transaction, we perform a full investigation with the blockchain, check all transactions to that address and do NOT automatically resend. A resend only occurs after we are sure the transaction did in fact not send (or a replacement transaction)
We also have no automated methods for moving funds from our safe wallets. Any time funds need to be moved from the safe wallet to the hot wallet - we perform a full audit to ensure everything is in balance.
We do not run on fractional reserves. We believe this would be a huge mistake for anybody in this business, as the markets are much too volatile. In many of our wallets we actually carry more funds than are committed to customer accounts. This way if we decide to delist a coin (which we do from time to time), then those funds are always available for immediate withdrawal.