CVE-2021-20826 Explained : Impact and Mitigation

A vulnerability labeled as CVE-2021-20826 has been discovered in IDEC PLC devices, specifically affecting versions such as the FC6A Series MICROSmart All-in-One CPU module v2.32 and earlier, FC6A Series MICROSmart Plus CPU module v1.91 and earlier, WindLDR v8.19.1 and earlier, WindEDIT Lite v1.3.1 and earlier, and Data File Manager v2.12.1 and earlier. This vulnerability could potentially allow attackers to intercept PLC Web server user credentials leading to unauthorized access and control over the PLC, enabling malicious activities.

Understanding CVE-2021-20826

This section delves into the intricacies of the CVE-2021-20826 vulnerability.

What is CVE-2021-20826?

The vulnerability in IDEC PLC devices enables unauthorized parties to capture user credentials transmitted between the PLC and associated software. This interception grants the attacker complete control over the PLC Web server, facilitating unauthorized actions such as output manipulation or PLC suspension.

The Impact of CVE-2021-20826

The exploitation of CVE-2021-20826 poses a severe threat as it grants unauthorized access to the PLC Web server, allowing attackers to manipulate systems and potentially disrupt operations.

Technical Details of CVE-2021-20826

This section outlines the technical aspects of the CVE-2021-20826 vulnerability.

Vulnerability Description

The vulnerability arises from unprotected transport of credentials in IDEC PLCs, making user credentials susceptible to interception during communication between the PLC and software.

Affected Systems and Versions

The vulnerability affects IDEC PLC devices running FC6A Series MICROSmart All-in-One CPU module v2.32 and earlier, FC6A Series MICROSmart Plus CPU module v1.91 and earlier, WindLDR v8.19.1 and earlier, WindEDIT Lite v1.3.1 and earlier, and Data File Manager v2.12.1 and earlier.

Exploitation Mechanism

Attackers exploit the vulnerability by intercepting communication between the PLC and software to obtain user credentials, subsequently gaining unauthorized access to the PLC Web server.

Mitigation and Prevention

Safeguarding measures to mitigate and prevent the CVE-2021-20826 vulnerability are crucial.

Immediate Steps to Take

Immediately updating to patched versions or implementing recommended security measures is essential to mitigate the risk posed by the vulnerability.

Long-Term Security Practices

Establishing robust security protocols, including network segmentation and user authentication mechanisms, can enhance the overall security posture.

Patching and Updates

Regularly applying security patches and updates provided by IDEC Corporation is imperative to address known vulnerabilities and enhance the security of IDEC PLC devices.