Disrupting a PyPI Software Supply Chain Attack

A researcher analyzed an emerging software supply chain attack on PyPI. Multiple packages lead them to a file on Github. One of them, msfpath, was the actual backdoor, and Snyk independently flagged it as a malicious package that opens a reverse shell to the attacker’s host. They reported the offending repo and in the meantime were able to follow improvements on the code the attacker pushed to the repo. Subsequently, they opened an issue on the repository “This is malware” together with information about PyPI sources. After a few hours of additional updates the attackers noticed their repo had been burned. Consequently, they pushed a commit deleting all the files from the repo. However, the commit history still contains all the information.