CVE-2018-16557 : Vulnerability Insights and Analysis

A security flaw has been discovered in multiple versions of the SIMATIC S7-400 CPU series, including various models such as CPU 412-1 DP V7, CPU 412-2 DP V7, CPU 414-2 DP V7, and others. The vulnerability exists in devices running versions prior to V7.0.3 for certain models. This flaw can be exploited by sending specially crafted packets to port 102/tcp through the Ethernet interface, PROFIBUS, or Multi Point Interfaces (MPI), potentially resulting in a denial of service (DoS) condition. To restore the affected CPU, it may be necessary to flash the firmware with a new image.

Exploiting this vulnerability requires the attacker to have network access to port 102/tcp via the Ethernet interface or the ability to send messages via PROFIBUS or Multi Point Interfaces (MPI) to the affected device. No user interaction is needed, and even without access protection configuration, the attacker does not require privileges to carry out the exploit. If successfully exploited, this vulnerability could lead to a DoS condition, compromising the system's availability and impacting its core functionality.

Understanding CVE-2018-16557

This CVE identifies a security vulnerability in multiple versions of the SIMATIC S7-400 CPU series, potentially leading to a denial of service (DoS) condition.

What is CVE-2018-16557?

The CVE-2018-16557 vulnerability is due to improper handling of packets on specific ports, allowing attackers to disrupt the affected devices' functionality.

The Impact of CVE-2018-16557

The exploitation of this vulnerability could result in a denial of service (DoS) condition, affecting the availability and core functionality of the impacted systems.

Technical Details of CVE-2018-16557

This section provides detailed technical information about the CVE-2018-16557 vulnerability.

Vulnerability Description

The vulnerability stems from the improper handling of packets on port 102/tcp through the Ethernet interface, PROFIBUS, or Multi Point Interfaces (MPI) in certain SIMATIC S7-400 CPU models.

Affected Systems and Versions

SIMATIC S7-400 CPU 412-1 DP V7
SIMATIC S7-400 CPU 412-2 DP V7
SIMATIC S7-400 CPU 414-2 DP V7
And other related models

Exploitation Mechanism

The vulnerability can be exploited by sending specially crafted packets to port 102/tcp through the Ethernet interface, PROFIBUS, or Multi Point Interfaces (MPI) in devices running versions prior to V7.0.3 for certain models.

Mitigation and Prevention

Protecting systems from CVE-2018-16557 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply vendor-supplied patches or firmware updates to mitigate the vulnerability.
Implement network segmentation to restrict access to critical ports and interfaces.
Monitor network traffic for any suspicious activity targeting port 102/tcp.

Long-Term Security Practices

Regularly update firmware and software to address known vulnerabilities.
Conduct security assessments and penetration testing to identify and remediate potential weaknesses.
Educate personnel on cybersecurity best practices to prevent unauthorized access.

Patching and Updates

Siemens may release patches or firmware updates to address the CVE-2018-16557 vulnerability. Stay informed about the availability of these updates and apply them promptly.