CVE-2023-28756 Explained : Impact and Mitigation

This CVE record pertains to a ReDoS (Regular Expression Denial of Service) vulnerability identified in the Time component in Ruby versions up to 3.2.1. The vulnerability occurs due to mishandling of invalid URLs with specific characters, leading to an increase in execution time when parsing strings to Time objects. The affected versions are up to 0.2.1, and the issue has been resolved in versions 0.1.1 and 0.2.2.

Understanding CVE-2023-28756

In this section, we will delve into what CVE-2023-28756 entails and its potential impact on systems.

What is CVE-2023-28756?

CVE-2023-28756 is a ReDoS vulnerability discovered in the Time component of Ruby versions up to 3.2.1. It arises from the incorrect handling of specific characters in invalid URLs, resulting in prolonged execution times during string parsing to Time objects.

The Impact of CVE-2023-28756

The impact of CVE-2023-28756 lies in its potential to be exploited by malicious actors to cause denial of service by significantly increasing system execution times. This vulnerability could be leveraged to disrupt services and impact the availability of affected systems.

Technical Details of CVE-2023-28756

This section will outline the technical aspects of CVE-2023-28756, including the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability in the Time component of Ruby versions through 3.2.1 allows for Regular Expression Denial of Service (ReDoS) attacks due to improper handling of specific characters in URLs, leading to extended execution times for parsing operations.

Affected Systems and Versions

The vulnerability affects versions of Ruby up to 3.2.1 and Time component versions up to 0.2.1. Systems running these versions are susceptible to exploitation if not promptly addressed.

Exploitation Mechanism

Malicious actors can exploit CVE-2023-28756 by crafting malicious requests with specially crafted URLs containing specific characters. When processed by the vulnerable Time component, these URLs can trigger ReDoS attacks, causing a significant increase in processing time and potentially leading to a denial of service.

Mitigation and Prevention

In this section, we will discuss the steps that can be taken to mitigate the impact of CVE-2023-28756 and prevent its exploitation.

Immediate Steps to Take

Users and administrators are advised to update their Ruby installations to the patched versions 0.1.1 or 0.2.2, where the vulnerability has been addressed.
Implement network-level protections to filter out potentially malicious requests that may exploit the ReDoS vulnerability.

Long-Term Security Practices

Regularly monitor for security advisories and updates from Ruby to stay informed about potential vulnerabilities and patches.
Conduct regular security audits and testing of web applications that utilize Ruby to identify and mitigate potential security weaknesses proactively.

Patching and Updates

Stay informed about security updates and patches released by Ruby maintainers to address vulnerabilities like CVE-2023-28756.
Promptly apply the latest patches to vulnerable systems to mitigate the risk of exploitation and ensure the security of your Ruby applications.