CVE-2021-40871 Explained : Impact and Mitigation

Softing Industrial Automation OPC UA C++ SDK before 5.66 allows remote attackers to cause a denial of service (DoS) by sending crafted messages to an OPC/UA client, leading to a process crash that requires a restart.

Understanding CVE-2021-40871

Softing Industrial Automation OPC UA C++ SDK is vulnerable to a DoS attack that can be triggered remotely via specially crafted messages.

What is CVE-2021-40871?

CVE-2021-40871 is a vulnerability found in Softing Industrial Automation OPC UA C++ SDK before version 5.66.
Attackers can exploit this issue to induce a DoS condition by sending malicious messages to an OPC/UA client.

The Impact of CVE-2021-40871

A successful exploit of this vulnerability can cause a denial of service, resulting in the crashing of the OPC/UA client's process.
This unexpected crash can disrupt operations and necessitate restarting the affected client application.

Technical Details of CVE-2021-40871

Softing Industrial Automation OPC UA C++ SDK's vulnerability includes the following technical details:

Vulnerability Description

The vulnerability allows remote attackers to execute a DoS attack through specially crafted messages.
The root cause of the issue lies in a wrong type cast that leads to a process crash.

Affected Systems and Versions

Product: Softing Industrial Automation OPC UA C++ SDK
Vendor: Softing
Versions Affected: All versions before 5.66

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specifically crafted messages to the targeted OPC/UA client, causing an unexpected process crash.

Mitigation and Prevention

It is crucial to take immediate steps and implement long-term security practices to mitigate the risks associated with CVE-2021-40871.

Immediate Steps to Take

Update the Softing Industrial Automation OPC UA C++ SDK to version 5.66 or newer to eliminate the vulnerability.
Monitor network traffic for any suspicious activity that could indicate exploitation attempts.

Long-Term Security Practices

Regularly update and patch software components to ensure the latest security fixes are in place.
Conduct security audits and penetration testing to identify and address any security loopholes.

Patching and Updates

Stay informed about security bulletins and advisories from Softing Industrial Automation.
Apply patches promptly to safeguard against known vulnerabilities and enhance system security.