CVE-2021-41817 : Vulnerability Insights and Analysis

CVE-2021-41817 is a vulnerability in the date gem through version 3.2.0 for Ruby, allowing for ReDoS (regular expression Denial of Service) through a long string. The fixed versions are 3.2.1, 3.1.2, 3.0.2, and 2.0.1.

Understanding CVE-2021-41817

What is CVE-2021-41817?

Date.parse in the date gem through 3.2.0 for Ruby is vulnerable to ReDoS, causing Denial of Service due to regular expression processing of long strings.

The Impact of CVE-2021-41817

This vulnerability could be exploited by an attacker to perform a Denial of Service attack, potentially disrupting the availability of affected systems.

Technical Details of CVE-2021-41817

Vulnerability Description

The vulnerability lies in how Date.parse handles long strings, allowing malicious actors to trigger a Denial of Service (DoS) by exploiting the regular expression processing.

Affected Systems and Versions

Systems using date gem up to version 3.2.0 for Ruby

Exploitation Mechanism

By sending a specially crafted long string, attackers can exploit the vulnerability, causing excessive processing time and resource consumption.

Mitigation and Prevention

Immediate Steps to Take

Update to the fixed versions: 3.2.1, 3.1.2, 3.0.2, or 2.0.1

Long-Term Security Practices

Regularly monitor for security updates and patches
Implement input validation to detect and block potentially malicious input

Patching and Updates

Stay informed about security advisories and updates from the Ruby community to promptly apply patches