CVE-2018-1000073 : Security Advisory and Response

A Directory Traversal vulnerability in RubyGems versions prior to Ruby 2.2.9, 2.3.6, 2.4.3, 2.5.0, and trunk revision 62422 allows path traversal when writing to a symlinked basedir outside of the root.

Understanding CVE-2018-1000073

This CVE involves a vulnerability in the install_location function of package.rb in RubyGems versions.

What is CVE-2018-1000073?

The vulnerability allows an attacker to perform path traversal by writing to a symlinked basedir outside of the root directory.

The Impact of CVE-2018-1000073

The vulnerability can be exploited to access sensitive files and directories outside the intended scope, potentially leading to unauthorized data disclosure or system compromise.

Technical Details of CVE-2018-1000073

The technical aspects of the vulnerability are as follows:

Vulnerability Description

The vulnerability exists in the install_location function of package.rb in RubyGems versions prior to specific releases, allowing path traversal outside the root.

Affected Systems and Versions

RubyGems versions prior to Ruby 2.2.9
Ruby 2.3.6
Ruby 2.4.3
Ruby 2.5.0
Trunk revision 62422

Exploitation Mechanism

Attackers can exploit this vulnerability by manipulating the symlinked basedir to traverse paths outside the root directory.

Mitigation and Prevention

To address CVE-2018-1000073, consider the following mitigation strategies:

Immediate Steps to Take

Update RubyGems to version 2.7.6 or later to patch the vulnerability.
Monitor and restrict access to sensitive directories.

Long-Term Security Practices

Regularly update software and libraries to the latest secure versions.
Implement proper input validation and sanitization to prevent path traversal attacks.

Patching and Updates

Apply patches provided by RubyGems to fix the vulnerability.
Stay informed about security advisories and updates from RubyGems and related vendors.