What are Weak Links in the npm Supply Chain? (2112.10165v2)

Abstract: Modern software development frequently uses third-party packages, raising the concern of supply chain security attacks. Many attackers target popular package managers, like npm, and their users with supply chain attacks. In 2021 there was a 650% year-on-year growth in security attacks by exploiting Open Source Software's supply chain. Proactive approaches are needed to predict package vulnerability to high-risk supply chain attacks. The goal of this work is to help software developers and security specialists in measuring npm supply chain weak link signals to prevent future supply chain attacks by empirically studying npm package metadata. In this paper, we analyzed the metadata of 1.63 million JavaScript npm packages. We propose six signals of security weaknesses in a software supply chain, such as the presence of install scripts, maintainer accounts associated with an expired email domain, and inactive packages with inactive maintainers. One of our case studies identified 11 malicious packages from the install scripts signal. We also found 2,818 maintainer email addresses associated with expired domains, allowing an attacker to hijack 8,494 packages by taking over the npm accounts. We obtained feedback on our weak link signals through a survey responded to by 470 npm package developers. The majority of the developers supported three out of our six proposed weak link signals. The developers also indicated that they would want to be notified about weak links signals before using third-party packages. Additionally, we discussed eight new signals suggested by package developers.

• The paper conducts a large-scale analysis of 1.63M npm packages to identify six weak link signals that increase supply chain risk.
• The analysis reveals vulnerabilities such as expired maintainer domains and risky installation scripts, with 93.9% of malicious packages using install scripts.
• Developer feedback supports alerts for three critical signals, emphasizing proactive measures to mitigate npm supply chain attacks.

Analyzing Weak Links in the npm Supply Chain

The paper "What are Weak Links in the npm Supply Chain?" explores the critical issue of supply chain security within the npm ecosystem, identifying potential vulnerabilities that could facilitate supply chain attacks. With a significant rise of 650% in supply chain attacks on open-source software, this research is pertinent to safeguarding the npm ecosystem by preemptively identifying possible security weaknesses.

The authors conducted a comprehensive analysis of metadata from 1.63 million JavaScript npm packages to propose six potential weak link signals within the npm supply chain. These weak link signals include:

1. Expired Maintainer Domain: This signal highlights the risk posed by maintainer accounts with email addresses linked to expired domains. Attackers could exploit these to hijack accounts.
2. Installation Scripts: Installation scripts can contain malicious code that executes during the package installation process, posing a significant threat vector.
3. Unmaintained Package: This refers to packages or maintainers that have been inactive, thereby increasing the risk of these packages being targeted by attackers.
4. Too Many Maintainers: Packages with numerous maintainers may fall prey to oversight and ease of access, potentially leading to unauthorized modifications.
5. Too Many Contributors: A large number of contributors may compromise the security if the maintainer does not effectively monitor and review code contributions.
6. Overloaded Maintainers: Maintainers with a large number of packages may not adequately secure all of them, exposing them to exploitation.

In one of the notable results, the authors found that 2,818 maintainer domains were available for purchase, posing a risk of potential hijacking for the associated packages. Furthermore, the analysis revealed that 2.2% of npm packages utilize install scripts despite their potential security risks, with 93.9% of known malicious packages deploying this vector.

The research integrates feedback from 470 npm package developers to validate these signals. The paper found majority support for three signals, with practitioners indicating a preference for notification about three out of the six proposed weak link signals before using third-party packages.

The implications of this research are significant. On a practical level, the identified weak link signals could guide developers and security specialists to prioritize efforts for risk mitigation. The paper underscores the need for proactive measures, such as enforcing two-factor authentication and monitoring email domain expirations, to enhance the npm ecosystem's resilience against supply chain attacks.

Theoretically, this research contributes to our understanding of the dynamic interplay between software supply chain structures and security vulnerabilities. It opens avenues for developing risk models and automated systems for identifying and mitigating supply chain vulnerabilities in real-time.

Future developments in artificial intelligence and machine learning can build upon this research by automating the detection of weak link signals across large-scale software ecosystems. These automated systems could offer real-time monitoring and alerts, assisting in preemptive actions against potential threats.

The paper's comprehensive framework and empirically validated signals lay a foundation for further exploration of supply chain vulnerabilities, with scope for application across other software ecosystems beyond npm. Such an expansion could provide a holistic understanding and robust defense against the escalating threat of supply chain attacks within the broader open-source community.