On September 18 released the latest version of software bitcoin wallet Bitcoin Core 0.16.3. It eliminates a critical error from double-spending, which can lead to a breakdown in all versions of Bitcoin Core that contains this bug. Bitcoin Core is the wallet software that is used by 94% of all bitcoin nodes, so updating to the latest version, it is important for the entire network of the main cryptocurrency.

It is assumed that the error was introduced accidentally with the release of Bitcoin Core 0.14.0. Then there was a potential risk that someone could double-use the same input for the same transaction, and if such data was broadcast to the network, each client Bitcoin Core to receive the transaction would crash.

However, this error can not be used by anyone other than miners who find blocks. If the miner will make double-spending, it would be tantamount to refusal of compensation for the mining unit at the rate of 12.5 bitcoins (about $80,000). So in reality such an attack is extremely unlikely (and vulnerability for quite a long time of the existence never been used), but in theory willing to cause harm to the network could destroy about 90% of all bitcoin nodes.

Failure did not succumb to those full nodes that work with the latest version of wallet, with predecessors, version 0.14.0, and also with the software, not specific to Bitcoin Core.

According to some, by September 19, only 1250 bitcoin nodes has been updated to version 0.16.3 Bitcoin Core, while there are 10,000 full bitcoin nodes. When there is a threat of decline in this indicator until 2000, if this bug will be used.

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