CVE-2019-6843 : Security Advisory and Response
Learn about CVE-2019-6843 affecting Modicon M580, M340, and BMxCRA/140CRA modules. Discover the impact, affected systems, exploitation method, and mitigation steps.
The Modicon M580, Modicon M340, and Modicon BMxCRA and 140CRA modules are affected by a CWE-755 vulnerability that can lead to a Denial of Service attack on the Programmable Logic Controller (PLC).
Understanding CVE-2019-6843
This CVE involves a vulnerability in the mentioned Schneider Electric products that could be exploited to disrupt PLC operations.
What is CVE-2019-6843?
The vulnerability in Modicon M580, Modicon M340, and Modicon BMxCRA / 140CRA modules allows attackers to trigger a Denial of Service attack by attempting to upgrade the controller with an empty firmware package via FTP.
The Impact of CVE-2019-6843
Exploiting this vulnerability could result in a complete disruption of the PLC's functionality, potentially leading to operational downtime and system unavailability.
Technical Details of CVE-2019-6843
This section provides more in-depth technical insights into the vulnerability.
Vulnerability Description
The vulnerability is categorized as CWE-755, indicating improper handling of exceptional conditions within the affected Schneider Electric products.
Affected Systems and Versions
- Modicon M580 firmware versions prior to V3.10
- All firmware versions of Modicon M340
- All firmware versions of Modicon BMxCRA and 140CRA modules
Exploitation Mechanism
Attackers can exploit the vulnerability by initiating a Denial of Service attack on the PLC through the FTP protocol while attempting to upgrade the controller with an empty firmware package.
Mitigation and Prevention
To address CVE-2019-6843 and enhance system security, consider the following mitigation strategies:
Immediate Steps to Take
- Apply patches or firmware updates provided by Schneider Electric.
- Implement network segmentation to isolate critical systems from potential attacks.
- Monitor network traffic for any suspicious activities that could indicate an ongoing exploit attempt.
Long-Term Security Practices
- Regularly update firmware and software to ensure the latest security patches are in place.
- Conduct security assessments and penetration testing to identify and address vulnerabilities proactively.
Patching and Updates
- Stay informed about security advisories and updates from Schneider Electric.
- Follow best practices for securely configuring and maintaining PLCs to reduce the attack surface.