On the Use of Refactoring in Security Vulnerability Fixes: An Exploratory Study on Maven Libraries

TL;DR

This study investigates how refactoring actions are used alongside security vulnerability fixes in Maven libraries, revealing that nearly one-third of fixes involve refactoring, which could inform future automated support tools.

Contribution

It provides the first empirical analysis of the relationship between refactoring and vulnerability fixes in real-world Maven libraries, highlighting the prevalence of refactoring in security fixes.

Findings

31.9% of vulnerability fixes involved refactoring

Refactoring is used to improve security fix quality

Potential for automated tools to support refactoring during security fixes

Abstract

Third-party library dependencies are commonplace in today's software development. With the growing threat of security vulnerabilities, applying security fixes in a timely manner is important to protect software systems. As such, the community developed a list of software and hardware weakness known as Common Weakness Enumeration (CWE) to assess vulnerabilities. Prior work has revealed that maintenance activities such as refactoring code potentially correlate with security-related aspects in the source code. In this work, we explore the relationship between refactoring and security by analyzing refactoring actions performed jointly with vulnerability fixes in practice. We conducted a case study to analyze 143 maven libraries in which 351 known vulnerabilities had been detected and fixed. Surprisingly, our exploratory results show that developers incorporate refactoring operations in their fixes, with 31.9% (112 out of 351) of the vulnerabilities paired with refactoring actions. We envision this short paper to open up potential new directions to motivate automated tool support, allowing developers to deliver fixes faster, while maintaining their code.