The bad actor's NPM account has since been deactivated, and all the three libraries, each of which were downloaded 112, 4, and 65 times respectively, have been removed from the repository as of October 15, 2021.
Attacks involving the three libraries worked by detecting the current operating system, before proceeding to run a .bat (for Windows) or .sh (for Unix-based OS) script. "These scripts then download an externally-hosted EXE or a Linux ELF, and execute the binary with arguments specifying the mining pool to use, the wallet to mine cryptocurrency for, and the number of CPU threads to utilize," Sonatype security researcher Ali ElShakankiry said.
Earlier this June, Sonatype and JFrog (formerly Vdoo) identified malicious packages infiltrating the PyPI repository that secretly deployed crypto-miners on the affected machines. This is notwithstanding copycat packages named after repositories or components used internally by high-profile tech companies in what's known as dependency confusion.