A new report by Kaspersky Labs claims a whopping 1.65 million infected computers are mining cryptocurrency for hackers. The security firm stresses it aren't just home PCs that are infected with cryptocurrency malware, but company servers as well.
Kaspersky claims Zcash and Monero are the most popular cryptocurrencies mined by malware. Bitcoin is of course a lot more popular but it's too unprofitable to mine on regular computers versus many altcoins.
"The main effect for a home computer or organization infrastructure is reduced system performance," Anton Ivanov, a security researcher for Kaspersky, wrote me in an email. "Also some miners could download modules from a threat actor's infrastructure, and these modules could contain other malware such as Trojans [malware that disguises itself as legitimate software]."
Users are advised to use security software to prevent infection. Signs you might be mining cryptocurrency for someone else may include inexplicably higher power consumption, suspicious slow-downs on your computer and way higher heat production.