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Vulnerability DatabaseCVE-2021-45936

CVE-2021-45936: 
Homebrew vulnerability analysis and mitigation

Overview

wolfSSL wolfMQTT 1.9 contains a heap-based buffer overflow vulnerability in MqttDecodeDisconnect function (called from MqttClientDecodePacket and MqttClient_WaitType). The vulnerability was discovered through OSS-Fuzz testing (OSS-Fuzz Issue).

Technical details

The vulnerability is classified as a heap-based buffer overflow WRITE operation occurring in the MqttDecodeDisconnect function. The issue is triggered when processing MQTT disconnect packets through the call chain of MqttClientDecodePacket and MqttClient_WaitType functions. The severity is rated as HIGH according to the ecosystem-specific assessment (OSS-Fuzz Vuln).

Impact

A heap-based buffer overflow vulnerability can lead to memory corruption, potentially allowing attackers to execute arbitrary code or cause denial of service conditions. The vulnerability affects the core MQTT protocol handling functionality, which could impact any application using the wolfMQTT library (OSS-Fuzz Vuln).

Mitigation and workarounds

The vulnerability has been fixed in commit 84d4b53122e0fa0280c7872350b89d5777dabbb2. Users should upgrade to a version of wolfMQTT that includes this fix. The vulnerability was introduced in commit 237f693c5731dcbd6adc9de69d9f575421c4414e (OSS-Fuzz Vuln).

Additional resources

Source: This report was generated using AI

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