CVE-2018-1000079 : Exploit Details and Defense Strategies

RubyGems versions prior to trunk revision 62422, including Ruby 2.2 series: 2.2.9 and earlier, 2.3 series: 2.3.6 and earlier, 2.4 series: 2.4.3 and earlier, 2.5 series: 2.5.0 and earlier, have a Directory Traversal vulnerability during gem installation, allowing writing files to any location on the filesystem.

Understanding CVE-2018-1000079

This CVE involves a critical vulnerability in RubyGems that could lead to unauthorized file writing during gem installation.

What is CVE-2018-1000079?

RubyGems versions prior to 2.7.6 are susceptible to a Directory Traversal vulnerability, enabling malicious gems to write files to any part of the filesystem during installation.

The Impact of CVE-2018-1000079

The vulnerability allows an attacker to exploit the gem installation process, potentially leading to unauthorized file writes on the system.

Technical Details of CVE-2018-1000079

RubyGems version Ruby 2.2 series: 2.2.9 and earlier, 2.3 series: 2.3.6 and earlier, 2.4 series: 2.4.3 and earlier, 2.5 series: 2.5.0 and earlier, prior to trunk revision 62422, contain a Directory Traversal vulnerability during gem installation.

Vulnerability Description

The vulnerability allows a malicious gem to write to arbitrary filesystem locations during installation, requiring the victim to install the compromised gem.

Affected Systems and Versions

Ruby 2.2 series: 2.2.9 and earlier
Ruby 2.3 series: 2.3.6 and earlier
Ruby 2.4 series: 2.4.3 and earlier
Ruby 2.5 series: 2.5.0 and earlier

Exploitation Mechanism

Exploiting this vulnerability involves the victim installing a malicious gem, which then gains unauthorized access to write files on the filesystem.

Mitigation and Prevention

To address CVE-2018-1000079, follow these steps:

Immediate Steps to Take

Update RubyGems to version 2.7.6 or later to mitigate the vulnerability.
Avoid installing gems from untrusted sources.

Long-Term Security Practices

Regularly update RubyGems and associated dependencies.
Implement code reviews to detect and prevent vulnerabilities in gems.

Patching and Updates

Ensure timely installation of security patches and updates to prevent exploitation of known vulnerabilities.