CVE-2021-20593 : Security Advisory and Response

This article provides detailed information about CVE-2021-20593, a vulnerability in Mitsubishi Electric Air Conditioning System/Centralized Controllers and Air Conditioning System/Expansion Controllers, allowing remote attackers to impersonate administrators.

Understanding CVE-2021-20593

CVE-2021-20593 is a vulnerability resulting from the incorrect implementation of the authentication algorithm in Mitsubishi Electric air conditioning systems, enabling attackers to disclose configuration information and tamper with system data.

What is CVE-2021-20593?

The vulnerability arises from a flaw in the authentication algorithm of Mitsubishi Electric air conditioning systems, allowing authenticated remote attackers to impersonate administrators.

The Impact of CVE-2021-20593

Exploiting this vulnerability enables attackers to access and manipulate critical system information and configurations, compromising the integrity and security of the air conditioning systems.

Technical Details of CVE-2021-20593

The vulnerability affects various versions of the Mitsubishi Electric Air Conditioning System/Centralized Controllers (G-50A, GB-50A, AG-150A, GB-50ADA, EB-50GU, AE-200A, AE-200E, AE-50A, AE-50E, EW-50A, EW-50E, TE-200A, TE-50A, TW-50A, CMS-RMD-J) and the Air Conditioning System/Expansion Controllers (PAC-YG50ECA).

Vulnerability Description

The flaw allows remote authenticated attackers to impersonate administrators, disclosing configuration information and tampering with the air conditioning system's operation data and configurations.

Affected Systems and Versions

Various versions are affected, including Ver.2.50 to Ver.3.35, Ver.3.20 and prior, Ver 7.09 and prior, and Ver 7.93 and prior.

Exploitation Mechanism

By exploiting this vulnerability, attackers can gain unauthorized access to sensitive configuration details, potentially leading to unauthorized control and disruption of air conditioning systems.

Mitigation and Prevention

To address CVE-2021-20593, users should take immediate steps and implement long-term security practices to protect their systems.

Immediate Steps to Take

Users are advised to apply security patches and updates provided by Mitsubishi Electric promptly to mitigate the vulnerability.

Long-Term Security Practices

Implement network segmentation, strong authentication mechanisms, and regular security audits to enhance the overall security posture of air conditioning systems.

Patching and Updates

Regularly monitor vendor advisories and apply security patches and updates to address vulnerabilities and enhance system security.