CVE-2017-1000047 in rbenv
Summary
by MITRE
rbenv (all current versions) is vulnerable to Directory Traversal in the specification of Ruby version resulting in arbitrary code execution
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Analysis
by VulDB Data Team • 03/07/2025
The vulnerability identified as CVE-2017-1000047 affects rbenv, a popular Ruby version management tool that allows developers to easily switch between multiple Ruby versions on the same system. This directory traversal flaw exists in how rbenv processes Ruby version specifications, creating a critical security risk that can be exploited by malicious actors to execute arbitrary code on affected systems. The vulnerability stems from insufficient input validation and path manipulation within rbenv's version handling mechanisms, making it particularly dangerous in development environments where rbenv is extensively used.
The technical flaw manifests when rbenv processes version specifications that contain directory traversal sequences such as ../ or ..\ which can manipulate the intended execution path. Attackers can craft malicious version strings that, when processed by rbenv, cause the tool to traverse directories beyond its intended scope and execute code from unexpected locations. This vulnerability is classified as a directory traversal attack pattern that aligns with CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory. The flaw exists at the core of rbenv's version resolution logic where it fails to properly sanitize or validate user-provided version specifications before using them to determine execution paths.
The operational impact of this vulnerability is severe and multifaceted across development and production environments. An attacker who can influence how rbenv resolves Ruby versions can potentially execute arbitrary code with the privileges of the user running rbenv, which typically includes developers and CI/CD systems. This risk extends beyond simple local exploitation as many development workflows involve automated tools that invoke rbenv, creating potential attack vectors for supply chain compromises. The vulnerability can be exploited through various attack vectors including malicious gem installations, compromised CI/CD pipelines, or social engineering attacks that trick developers into executing malicious version specifications. According to ATT&CK framework, this vulnerability maps to T1059.001 for command and scripting interpreter and T1210 for exploitation of remote services, as it enables arbitrary code execution through legitimate system interfaces.
Mitigation strategies for CVE-2017-1000047 require immediate action to address the root cause through proper input validation and path sanitization. The most effective immediate solution is to upgrade to a patched version of rbenv that properly validates version specifications and implements proper path traversal protections. Organizations should also implement strict access controls and input validation for any automated processes that utilize rbenv, particularly in CI/CD environments where version specifications might come from untrusted sources. Security monitoring should be enhanced to detect unusual rbenv usage patterns and potentially malicious version specifications. Additionally, developers should be trained to avoid using untrusted version specifications and to verify the integrity of any Ruby version declarations in their workflows. The vulnerability highlights the importance of proper input validation in system tools and demonstrates how seemingly benign path manipulation can lead to critical security breaches, making it essential for organizations to maintain up-to-date security practices and vulnerability management processes.