CVE-2021-33446 Explained : Impact and Mitigation

An issue was discovered in mjs (mJS: Restricted JavaScript engine), ES6 (JavaScript version 6), leading to a NULL pointer dereference in mjs_next() in mjs.c.

Understanding CVE-2021-33446

This CVE highlights a vulnerability in the mjs (mJS) JavaScript engine that can be exploited through a NULL pointer dereference.

What is CVE-2021-33446?

CVE-2021-33446 refers to a specific vulnerability found in the mjs (mJS) JavaScript engine which allows attackers to trigger a NULL pointer dereference in the code.

The Impact of CVE-2021-33446

This vulnerability could potentially be exploited by malicious actors to cause denial of service (DoS) attacks or potentially execute arbitrary code on affected systems.

Technical Details of CVE-2021-33446

Here are key technical details related to the CVE:

Vulnerability Description

The vulnerability exists in the mjs_next() function in mjs.c, where a NULL pointer dereference can be triggered.

Affected Systems and Versions

The issue affects instances running mjs (mJS) with ES6 (JavaScript version 6).

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting specific input that can lead to the NULL pointer dereference in the mjs_next() function.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-33446, consider the following steps:

Immediate Steps to Take

Update the mjs (mJS) engine to a patched version provided by the vendor.
Restrict network access to vulnerable systems.

Long-Term Security Practices

Regularly monitor vendor security advisories for updates.
Implement strong input validation mechanisms to prevent NULL pointer dereference vulnerabilities.

Patching and Updates

Ensure that your software is up to date with the latest patches and security fixes to address CVE-2021-33446.