Well Begun is Half Done: An Empirical Study of Exploitability & Impact of Base-Image Vulnerabilities (2112.12597v1)

Abstract: Container technology, (e.g., Docker) is being widely adopted for deploying software infrastructures or applications in the form of container images. Security vulnerabilities in the container images are a primary concern for developing containerized software. Exploitation of the vulnerabilities could result in disastrous impact, such as loss of confidentiality, integrity, and availability of containerized software. Understanding the exploitability and impact characteristics of vulnerabilities can help in securing the configuration of containerized software. However, there is a lack of research aimed at empirically identifying and understanding the exploitability and impact of vulnerabilities in container images. We carried out an empirical study to investigate the exploitability and impact of security vulnerabilities in base-images and their prevalence in open-source containerized software. We considered base-images since container images are built from base-images that provide all the core functionalities to build and operate containerized software. We discovered and characterized the exploitability and impact of security vulnerabilities in 261 base-images, which are the origin of 4,681 actively maintained official container images in the largest container registry, i.e., Docker Hub. To characterize the prevalence of vulnerable base-images in real-world projects, we analysed 64,579 containerized software from GitHub. Our analysis of a set of $1,983$ unique base-image security vulnerabilities revealed 13 novel findings. These findings are expected to help developers to understand the potential security problems related to base-images and encourage them to investigate base-images from security perspective before developing their applications.

• The paper systematically analyzes 1,983 vulnerabilities across 261 base-images, revealing high exploitability and severe impact risks.
• It employs rigorous methodologies with tools like ANCHORE and the NVD to assess attack complexity and monitor vulnerability propagation.
• The findings show that 91.6% of GitHub containerized projects rely on vulnerable images, underlining an urgent need for improved patch management.

Analysis of Exploitability and Impact of Base-Image Vulnerabilities in Containerized Software

The paper "Well Begun is Half Done: An Empirical Study of Exploitability Impact of Base-Image Vulnerabilities" explores the critical issue of security vulnerabilities in container images, with a particular focus on the base-images which serve as the foundational layers for widespread containerized applications. The growing adoption of container technologies, exemplified by platforms such as Docker, has brought attention to the unique challenges posed by vulnerability management within container environments.

Core Contributions

The paper conducts an empirical analysis aimed at understanding the exploitability and impact characteristics of vulnerabilities found in base-images stored on Docker Hub (DH). The research identifies 261 base-images originating from 4,681 active DH official images, which were then explored for security vulnerabilities through a rigorous methodology that employed industry-standard tools and databases, including ANCHORE and the National Vulnerability Database (NVD).

Key Findings

1. Vulnerability Landscape:
   • The paper discovered 1,983 unique base-image security vulnerabilities.
   • A significant portion of these vulnerabilities presented characteristics of high exploitability (59.7% in minimal base-images like alpine) and high impact (46.9% in large OS base-images like debian).
2. Exploitability and Attack Vectors:
   • Base-images from minimal repositories were more susceptible to external attacks due to their high presence of network-based exploitability, while large OS base-images were more prone to vulnerabilities exploitable by internal attackers.
   • The vulnerabilities exhibited varying levels of attack complexity, privileges required, and user interaction, with a larger share being easily exploitable.
3. Impact Analysis:
   • The potential impacts on confidentiality, integrity, and availability (CIA) were disproportionately high for certain vulnerabilities, especially in bash and busybox base-images.
   • The propagation of vulnerabilities from base-images to derived containerized applications is a substantial risk factor, with many routine vulnerabilities remaining unpatched due to inadequate update practices.
4. Prevalence in Open-Source Projects:
   • An extensive investigation into 64,579 GitHub projects revealed that 91.6% of containerized applications are based on vulnerable base-images, illustrating the widespread reliance on potentially insecure foundational layers.
5. Presence of Proof-of-Concept (PoC) Exploits:
   • The existence of PoC exploits in DH's official base-images enhances the urgency for improved vulnerability management and patching processes.

Implications

The paper's findings have profound implications for multiple stakeholders within the software development landscape:

• Developers are encouraged to meticulously assess base-image vulnerabilities before adopting them for application development, prioritizing images with minimal High Exploitability (HE) or High Impact (HI) vulnerabilities.
• Security Tool Builders can enhance their offerings by integrating exploitability metrics and exposure time measurement to assist developers in real-time risk assessment.
• Researchers are provided with a dataset and baseline analysis which could foster investigation into mitigation strategies and predictive models for vulnerability detection and patch application.

Future Directions

The paper sets the stage for promising future research directions. There is a pronounced need for the creation of automated tools and frameworks that can assist in selecting optimal base-images and recommending real-time patches. Furthermore, integration of advanced machine learning approaches to predict vulnerability fixes presents a compelling avenue for exploration.

Ultimately, this paper underscores the critical importance of securing the foundational layers of containerized applications, without which the entire software ecosystem remains in jeopardy of exploitation. The insights furnished by this paper can guide the ongoing endeavors to fortify container infrastructure against prevalent security vulnerabilities.