Trezor, the popular cryptocurrency hardware wallet, wants to bring to light the problem of Bitcoin malware, where a parasitic computer virus uses your excess computing power to mine Bitcoin on someone elses behalf. Trezor brings to light an important and sometimes overshadowed issue in the Bitcoin community, parasitic Bitcoin mining malware. Bitcoin mining is a process of transaction verification where a user uses computing power in order to solve a mathematically equation to prove the legitimacy of a block of transactions. The first user to correctly solve the problem is rewarded in BTC for putting in the work to verify the transaction. While this process is meant to reward the owner and user of the computing power, it is possible for someone to take over your computer using malware and use it to stealthily mine Bitcoin for themselves on your behalf. This concept, sometimes known as "cryptojacking" can infect your computer easily if you are not careful, and is possible to be downloaded from an unsolicited email or even a malicious website that implants mining scripts in the page itself. If your electric bill is higher than usual, your computer is slower, or you are noticing other odd behaviors on your computer, make sure it is not infected with malware and that another entity is not using your computing power to mine Bitcoin for themselves. This is an act of theft and should not be tolerated or reacted to lightly.