CVE-2021-22883 : Security Advisory and Response

Node.js before versions 10.24.0, 12.21.0, 14.16.0, and 15.10.0 are susceptible to a denial of service vulnerability due to a leak of file descriptors caused by too many connection attempts with an 'unknownProtocol'. The impact includes server unavailability due to a file descriptor leak or excessive memory usage leading to system out-of-memory crashes.

Understanding CVE-2021-22883

This section delves into the details of the Node.js vulnerability.

What is CVE-2021-22883?

CVE-2021-22883 is a denial of service vulnerability in Node.js that arises when numerous connection attempts with an 'unknownProtocol' are established, resulting in a file descriptor leak.

The Impact of CVE-2021-22883

The vulnerability can cause a server to be unable to accept new connections, leading to unavailability, or result in excessive memory consumption, potentially causing system crashes due to memory exhaustion.

Technical Details of CVE-2021-22883

This section explores the technical aspects of the CVE.

Vulnerability Description

The vulnerability in Node.js allows for a denial of service attack through excessive connection attempts with an 'unknownProtocol', resulting in a file descriptor leak.

Affected Systems and Versions

Node.js versions before 10.24.0, 12.21.0, 14.16.0, and 15.10.0 are affected by this vulnerability.

Exploitation Mechanism

Attackers can exploit this vulnerability by establishing too many connection attempts with an 'unknownProtocol', leading to file descriptor leaks.

Mitigation and Prevention

This section focuses on mitigating the risks associated with CVE-2021-22883.

Immediate Steps to Take

Users are advised to update their Node.js installations to versions 10.24.0, 12.21.0, 14.16.0, or 15.10.0 to mitigate the denial of service risk.

Long-Term Security Practices

Implement file descriptor limits on the system to prevent server unavailability and practice secure coding to reduce vulnerability exploitation possibilities.

Patching and Updates

Regularly update Node.js to the latest versions to ensure that known vulnerabilities are patched and security is enhanced.