CVE-2020-10663 : Security Advisory and Response

CVE-2020-10663, known as the Unsafe Object Creation Vulnerability in the JSON gem for Ruby, poses a security risk in various Ruby versions. This vulnerability allows the creation of malicious objects within the interpreter, potentially leading to application-dependent adverse effects.

Understanding CVE-2020-10663

This CVE highlights a vulnerability in the JSON gem used in multiple Ruby versions, enabling the creation of harmful objects within the interpreter.

What is CVE-2020-10663?

The JSON gem through version 2.2.0 for Ruby, utilized in Ruby 2.4 through 2.6.5, contains an Unsafe Object Creation Vulnerability. Unlike a previous CVE, this issue does not rely on Ruby's garbage-collection behavior but on JSON parsing methods that can generate malicious objects.

The Impact of CVE-2020-10663

The vulnerability allows attackers to craft JSON payloads that, when parsed, create harmful objects within the Ruby interpreter. The consequences of this exploit vary based on the affected application.

Technical Details of CVE-2020-10663

This section delves into the specifics of the CVE, including the vulnerability description, affected systems, versions, and the exploitation mechanism.

Vulnerability Description

The JSON gem in Ruby versions 2.4 to 2.6.5 is susceptible to an Unsafe Object Creation Vulnerability. By manipulating JSON parsing methods, attackers can introduce malicious objects into the interpreter.

Affected Systems and Versions

Ruby 2.4 to 2.4.9
Ruby 2.5 to 2.5.7
Ruby 2.6 to 2.6.5

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting specially designed JSON payloads that, upon parsing, trigger the creation of harmful objects within the Ruby interpreter.

Mitigation and Prevention

Protecting systems from CVE-2020-10663 involves immediate actions and long-term security practices.

Immediate Steps to Take

Update Ruby to a patched version that addresses the vulnerability.
Avoid parsing untrusted JSON data until the system is patched.

Long-Term Security Practices

Regularly update Ruby and its dependencies to mitigate future vulnerabilities.
Implement input validation and sanitization to prevent malicious JSON payloads.

Patching and Updates

Ensure that all systems running affected Ruby versions are promptly patched with the latest updates to mitigate the CVE-2020-10663 vulnerability.