CVE-2019-10943 : Security Advisory and Response

A vulnerability has been identified in various Siemens products including SIMATIC Drive Controller family, SIMATIC ET 200SP Open Controller CPU 1515SP PC, SIMATIC S7-1200 CPU family, SIMATIC S7-1500 CPU family, SIMATIC S7-1500 Software Controller, and SIMATIC S7-PLCSIM Advanced. This vulnerability allows an attacker with network access to potentially modify the user program on the PLC, impacting the integrity of the user program stored on the CPU.

Understanding CVE-2019-10943

This CVE involves a vulnerability that could lead to unauthorized modification of user programs on Siemens devices.

What is CVE-2019-10943?

The vulnerability allows attackers with network access to port 102/tcp to alter user programs on affected devices, potentially causing discrepancies between the running code and the source code stored on the device.

The Impact of CVE-2019-10943

The vulnerability could result in the integrity of the user program being compromised, leading to discrepancies between the actual running code and the source code stored on the device.

Technical Details of CVE-2019-10943

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability allows attackers to modify user programs on Siemens devices, impacting the integrity of the stored user program.

Affected Systems and Versions

SIMATIC Drive Controller family: All versions
SIMATIC ET 200SP Open Controller CPU 1515SP PC: All versions
SIMATIC S7-1200 CPU family: < V4.4.0 and >= V4.4.0
SIMATIC S7-1500 CPU family: < V2.8.1 and >= V2.8.1
SIMATIC S7-1500 Software Controller: < V20.8 and >= V20.8
SIMATIC S7-PLCSIM Advanced: < V3.0 and >= V3.0

Exploitation Mechanism

To exploit this vulnerability, attackers need network access to affected devices and the ability to make changes to the user program, allowing them to modify the running code on the PLC.

Mitigation and Prevention

Protecting against and addressing the CVE-2019-10943 vulnerability.

Immediate Steps to Take

Implement network segmentation to restrict access to critical devices.
Monitor network traffic for any unauthorized access attempts.
Apply the latest security patches and updates from Siemens.

Long-Term Security Practices

Regularly update and patch all Siemens devices to mitigate known vulnerabilities.
Conduct security training for personnel to recognize and respond to potential threats.

Patching and Updates

Siemens may release patches or updates to address the vulnerability. Stay informed about security advisories and apply patches promptly.