CVE-2022-30938 : Security Advisory and Response

A vulnerability has been identified in multiple variants of Siemens EN100 Ethernet modules, potentially leading to a denial of service condition when exploited.

Understanding CVE-2022-30938

This CVE involves a memory corruption vulnerability in several EN100 Ethernet module variants due to improper handling of crafted HTTP packets.

What is CVE-2022-30938?

The vulnerability affects Siemens' EN100 Ethernet modules, including DNP3 IP, IEC 104, IEC 61850, Modbus TCP, and PROFINET IO variants. It allows attackers to crash affected applications, resulting in denial of service.

The Impact of CVE-2022-30938

Exploitation of this vulnerability can lead to a complete system crash and disrupt critical operations relying on these Ethernet modules. Attackers can remotely trigger the vulnerability by sending malicious HTTP packets.

Technical Details of CVE-2022-30938

The following technical details outline the vulnerability and its implications.

Vulnerability Description

The flaw arises from a memory corruption issue triggered by manipulating a specific argument in crafted HTTP packets directed to the /txtrace endpoint of affected EN100 Ethernet modules.

Affected Systems and Versions

All versions of EN100 Ethernet modules across DNP3 IP, IEC 104, Modbus TCP, and PROFINET IO variants are affected. Notably, the IEC 61850 variant versions below V4.40 are also vulnerable.

Exploitation Mechanism

By sending specially crafted HTTP packets targeting the /txtrace endpoint with manipulated arguments, threat actors can exploit this vulnerability to cause the target application to crash, leading to a denial of service scenario.

Mitigation and Prevention

Understanding how to mitigate and prevent CVE-2022-30938 is crucial to safeguard affected systems and networks.

Immediate Steps to Take

Immediately apply security patches or updates provided by Siemens to address the vulnerability in EN100 Ethernet modules. Ensure that all systems are up to date to eliminate the risk of exploitation.

Long-Term Security Practices

Incorporate regular security audits, network monitoring, and training for personnel to enhance overall cybersecurity posture. Implement network segmentation and access controls to limit exposure to potential threats.

Patching and Updates

Stay informed about security advisories and updates from Siemens regarding the EN100 Ethernet modules. Regularly check for patches and apply them promptly to mitigate risks associated with known vulnerabilities.