What is it?
Bitcoin mining is the process of adding transaction records to Bitcoin's public ledger of past transactions or blockchain. This ledger of past transactions is called the block chain as it is literally a chain of blocks that serves to confirm transactions to the rest of the network as having taken place. Bitcoin nodes use the block chain to distinguish legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere. The primary purpose of mining therefore is to allow Bitcoin nodes to reach a secure, tamper-resistant consensus. Additionally, the miner is awarded the fees paid by users sending transactions. The fee is an incentive for the miner to include the transaction in their block. In the future, as the number of new bitcoins miners are allowed to create in each block dwindles, the fees will make up a much higher percentage of mining income.
Cryptojacking is the unauthorised use of someone else’s computer to mine cryptocurrency – i.e. hacking bitcoins and other digital currencies.
Why is it a threat?
Rogue miners steal other people’s computer power. The possibility of compensation is what attracts miners, but it’s the need for computer capacity to solve the hash that leads miners to ‘leverage’ enterprise resources. They do this using Trojan malware that runs on the affected host machine and does bitcoin mining in the background, often without the user being aware of the ‘parasite within’.