CVE-2021-44531 Explained : Impact and Mitigation

Node.js vulnerability allowing bypassing name-constrained intermediates due to improper Certificate Validation.

Understanding CVE-2021-44531

What is CVE-2021-44531?

The vulnerability in Node.js versions <12.22.9, <14.18.3, <16.13.2, and <17.3.1 allowed acceptance of URI SAN types, potentially leading to bypassing name-constrained intermediates.

The Impact of CVE-2021-44531

Accepting arbitrary Subject Alternative Name (SAN) types without PKI specification could result in security bypasses. URI SAN types, not commonly specified in PKIs, could be accepted leading to incorrect URI matching.

Technical Details of CVE-2021-44531

Vulnerability Description

Node.js versions prior to 12.22.9, 14.18.3, 16.13.2, and 17.3.1 were vulnerable to improper URI SAN type acceptance, potentially impacting security.

Affected Systems and Versions

Versions of Node.js <12.22.9, <14.18.3, <16.13.2, <17.3.1

Exploitation Mechanism

Lack of proper URI SAN type validation

Mitigation and Prevention

Immediate Steps to Take

Update Node.js to version 12.22.9, 14.18.3, 16.13.2, 17.3.1 or higher
Utilize the --security-revert command-line option if needed

Long-Term Security Practices

Define and enforce PKI policies for SAN types
Regularly review and update certificate handling mechanisms

Patching and Updates

Node.js versions 12.22.9, 14.18.3, 16.13.2, and 17.3.1 include fixes for the vulnerability