CVE-2021-21868 : Security Advisory and Response

An unsafe deserialization vulnerability exists in the ObjectManager.plugin Project.get_MissingTypes() functionality of CODESYS GmbH CODESYS Development System versions 3.5.16 and 3.5.17. This vulnerability could allow an attacker to execute arbitrary commands by providing a specially crafted file.

Understanding CVE-2021-21868

This section provides insights into the nature and impact of CVE-2021-21868.

What is CVE-2021-21868?

The vulnerability CVE-2021-21868 is associated with an unsafe deserialization flaw within the ObjectManager.plugin Project.get_MissingTypes() feature of CODESYS GmbH CODESYS Development System versions 3.5.16 and 3.5.17. Attackers exploiting this vulnerability can potentially execute malicious commands on the system.

The Impact of CVE-2021-21868

The impact of CVE-2021-21868 is rated with a CVSS base score of 8.8, classifying it as a high severity issue. The vulnerability could lead to significant availability, confidentiality, and integrity impacts, with no privileges required for exploitation.

Technical Details of CVE-2021-21868

This section discusses the technical aspects of CVE-2021-21868 in detail.

Vulnerability Description

The vulnerability lies in the deserialization function of the ObjectManager.plugin Project.get_MissingTypes() in CODESYS Development System versions 3.5.16 and 3.5.17. An attacker can leverage a malicious file to trigger arbitrary command execution.

Affected Systems and Versions

The affected systems include CODESYS GmbH CODESYS Development System versions 3.5.16 and 3.5.17.

Exploitation Mechanism

Exploiting this vulnerability requires an attacker to provide a specially crafted file to the target system, triggering the arbitrary command execution.

Mitigation and Prevention

To protect systems from CVE-2021-21868, immediate steps should be taken alongside long-term security practices.

Immediate Steps to Take

Update to the latest patched versions of CODESYS Development System to mitigate the vulnerability.
Avoid opening untrusted files or code from unknown sources.
Implement network security measures to detect and prevent malicious file uploads.

Long-Term Security Practices

Regularly update software and firmware to ensure the latest security patches are applied.
Conduct security training for employees to raise awareness about safe handling of files and data.
Employ defense-in-depth strategies to enhance overall system security.

Patching and Updates

Stay informed about security advisories and patches released by CODESYS GmbH to address vulnerabilities like CVE-2021-21868.