CVE-2021-41039 : Exploit Details and Defense Strategies

Eclipse Mosquitto versions 1.6 to 2.0.11 may experience excessive CPU usage and potential denial of service due to a vulnerability in handling MQTT v5 clients with numerous user-property properties.

Understanding CVE-2021-41039

In this section, we will delve into the details of CVE-2021-41039.

What is CVE-2021-41039?

CVE-2021-41039 relates to a flaw in Eclipse Mosquitto versions 1.6 to 2.0.11 that enables a significant CPU usage increase and potential performance degradation or denial of service when an MQTT v5 client connects with a large number of user-property properties.

The Impact of CVE-2021-41039

The impact of this CVE includes a possible denial of service due to excessive CPU usage, impacting system performance.

Technical Details of CVE-2021-41039

Exploring the technical aspects of CVE-2021-41039.

Vulnerability Description

The vulnerability in Eclipse Mosquitto versions 1.6 to 2.0.11 allows MQTT v5 clients with numerous user-property properties to cause high CPU consumption, potentially leading to denial of service.

Affected Systems and Versions

Vendor: The Eclipse Foundation
Product: Eclipse Mosquitto
Vulnerable Versions:
Version 1.6 (affected)
Versions less than or equal to 2.0.11 (affected)

Exploitation Mechanism

The vulnerability can be exploited by an MQTT v5 client connecting with a substantial number of user-property properties, triggering excessive CPU usage.

Mitigation and Prevention

Guidelines for mitigating and preventing the CVE-2021-41039 vulnerability.

Immediate Steps to Take

Upgrade Eclipse Mosquitto to a patched version.
Limit the number of user-property properties in MQTT v5 clients.

Long-Term Security Practices

Regularly update and monitor MQTT client configurations.
Implement network security measures to detect and prevent potential denial of service attacks.

Patching and Updates

Patch Eclipse Mosquitto to the latest version available to address the CVE-2021-41039 vulnerability.