CVE-2021-32773 : Security Advisory and Response

Racket is a general-purpose programming language with an ecosystem for language-oriented programming. A vulnerability in versions prior to 8.2 allows a confused deputy attack in sandbox module resolution, potentially enabling attackers to control system functions.

Understanding CVE-2021-32773

This CVE describes a security vulnerability in Racket versions before 8.2 that could lead to a confused deputy attack, impacting system modules used by the Racket sandbox.

What is CVE-2021-32773?

In versions prior to 8.2, code evaluated in the Racket sandbox could result in system modules incorrectly utilizing attacker-created modules instead of their intended dependencies. This could grant attackers control over system functions, bypassing intended restrictions.

The Impact of CVE-2021-32773

The vulnerability's CVSS base score is 6.1, with high integrity impact, network attack complexity, and user interaction required. Attackers could exploit this issue to compromise system functions.

Technical Details of CVE-2021-32773

This section provides a detailed technical overview of the vulnerability.

Vulnerability Description

The flaw allows malicious actors to manipulate system modules in Racket, potentially leading to the execution of unauthorized actions.

Affected Systems and Versions

Racket versions prior to 8.2 are impacted by this vulnerability, exposing systems to the confused deputy attack.

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting code evaluated within the Racket sandbox to gain control over system modules.

Mitigation and Prevention

To protect your systems from CVE-2021-32773, follow these recommended security measures.

Immediate Steps to Take

Upgrade Racket to version 8.2 or newer to address this vulnerability. For systems with arbitrary Racket evaluation, consider using external sandboxing mechanisms for enhanced security.

Long-Term Security Practices

Implement secure coding practices, regularly update Racket and apply security patches promptly to mitigate the risk of such vulnerabilities.

Patching and Updates

Stay informed about security advisories and updates from the Racket project to apply patches as soon as they become available.