CVE-2021-29446 Explained : Impact and Mitigation

A vulnerability known as Padding Oracle Attack due to Observable Timing Discrepancy was discovered in jose-node-cjs-runtime, affecting versions prior to 3.11.4. The vulnerability could allow an attacker to decrypt data without knowing the decryption key. This article provides insights into the impact, technical details, and mitigation steps related to CVE-2021-29446.

Understanding CVE-2021-29446

This section dives into the details of the vulnerability in jose-node-cjs-runtime.

What is CVE-2021-29446?

jose-node-cjs-runtime, an npm package providing cryptographic functions, before version 3.11.4, was susceptible to a Padding Oracle Attack due to observable timing discrepancies. This flaw could enable an adversary to decrypt data without knowledge of the decryption key.

The Impact of CVE-2021-29446

The CVE scored a base severity of MEDIUM, with a CVSS base score of 5.9. The vulnerability's confidentiality impact was rated as HIGH, making it crucial for affected users to take immediate action.

Technical Details of CVE-2021-29446

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

In versions preceding 3.11.4, jose-node-cjs-runtime mishandled the AES_CBC_HMAC_SHA2 Algorithm decryption process, potentially leading to a padding oracle attack due to observable timing discrepancies.

Affected Systems and Versions

The vulnerability impacts jose-node-cjs-runtime versions below 3.11.4.

Exploitation Mechanism

An adversary could exploit the timing differences during decryption to orchestrate a padding oracle attack, decrypting data without access to the decryption key.

Mitigation and Prevention

Learn how to mitigate the risks associated with CVE-2021-29446.

Immediate Steps to Take

Affected users are strongly advised to upgrade to jose-node-cjs-runtime version 3.11.4 or newer to prevent exploitation of the vulnerability.

Long-Term Security Practices

Ensure regular updates and monitoring of security advisories to stay protected from similar vulnerabilities in the future.

Patching and Updates

Stay proactive in applying patches and updates to mitigate the risk of known vulnerabilities.