This paper presents results from the MSR 2021 Hackathon. Our team investigates files/projects that contain known security vulnerabilities and how widespread they are throughout repositories in open source software. These security vulnerabilities can potentially be propagated through code reuse even when the vulnerability is fixed in different versions of the code. We utilize the World of Code [1] infrastructure to discover file-level duplication of code from a nearly complete collection of open source software. This paper describes a method and set of tools to find all open source projects that use known vulnerable files and any previous revisions of those files.

The introduction of Git 1 , a version control system, has radically changed the software development process. Currently, Git is considered an essential skill for software engineering developers and is necessary for collaboration between developers [1] . This reliance on Git means that software development creates a vast pool of publicly available data. This data provides an opportunity for software engineering researchers interested in analyzing the software development process. Such analysis could facilitate numerous tools for developers that substantially increase developer productivity.