A recent study conducted by Massachusetts-based cloud-native security firm Aqua has shed light on a concerning vulnerability present in millions of software repositories hosted on GitHub. This vulnerability, dubbed RepoJacking, poses a significant threat to repositories belonging to esteemed organizations like Google, Lyft, and numerous others. 

RepoJacking involves the exploitation of vulnerabilities within GitHub repositories, potentially allowing malicious actors to gain unauthorized access and manipulate the code stored within. This vulnerability could have far-reaching consequences, including the compromise of sensitive data, the introduction of malicious code, and the disruption of software development processes. 

Think of GitHub repositories as digital filing cabinets where developers store their code and project files. These cabinets use a system called Git to track changes made to the code over time and allow multiple developers to collaborate on the same project. However, if a hacker gains control of a GitHub repository, it can spell trouble. 

They could sneak in harmful code, swipe important data, disrupt the project's progress, or trick other developers into using their compromised code. This could lead to serious security breaches, data leaks, and project delays. So, it becomes crucial for developers to safeguard their repositories and carefully manage who has access to them. 

Supply chain vulnerability, also referred to as dependency repository hijacking (RepoJacking), poses a significant threat to software security. In this form of attack, malicious actors exploit previously owned organizations or user names to distribute compromised versions of software repositories. These altered repositories may contain hidden malware, allowing attackers to perform harmful actions on systems where the tainted software is installed. 

The vulnerability arises from a flaw in the process when a repository owner decides to change their username. Although a connection is created between the old and new usernames to ensure continuity for users relying on dependencies from the old repository, this connection can be exploited by anyone who claims the old username. This loophole enables the injection of malicious code into the repository without detection. 

This type of supply-chain attack has been observed since at least 2016, when a college student uploaded custom scripts to popular package repositories like RubyGems, PyPi, and NPM, posing as legitimate packages. This technique, known as typosquatting, takes advantage of users' mistakes when selecting package names. 

Similarly, in 2021, a researcher employed a technique called dependency confusion or namespace confusion attack to breach the networks of major companies such as Apple, Microsoft, and Tesla. This involved placing malicious code packages with the same names as genuine dependencies used by the targeted companies, allowing the counterfeit code to be automatically downloaded and installed by the companies' package managers.