Consumers have found a bug in Bitcoin “time-barred” contracts that could potentially allow miners to steal BTCs from each other.
Anonymous crypto engineer 0xb10c reports that it has detected more than one million time-locked transactions made between September 2019 and March 2020. The publication 0xb10c describes in detail how these special Bitcoin transactions are not properly enforced by the network.
Unlike normal transactions, time-locked transactions prevent the received Bitcoin from being accessed after it has been sent. Users must wait a certain number of blocks to be added to the network at ten-minute intervals before gaining control of their Bitcoin.
0xb10c claims that time-lost locked transactions provide a vector for miners to attack in order to steal transaction fees from each other by “charging”. According to the engineer, the backlog of time-barred transactions was purposefully designed for a “potentially destructive extraction strategy” involving the theft of mining fees.
In an interview with CoinDesk, 0xb10c said that time-locked transactions were a low-priority problem that could eventually be included in the wider network. He explained that the withdrawal of fees will become more profitable in a few years, as most of the miner’s income goes to transaction fees.
A fix for this was released in early 2020. However, it will take some time before all instances of the current software are updated.