CVE-2020-12526: BECKHOFF: DoS-Vulnerability for TwinCAT OPC UA Server and IPC Diagnostics UA Server

Published May 13, 2021
·
Updated

TwinCAT OPC UA Server in versions up to 2.3.0.12 and IPC Diagnostics UA Server in versions up to 3.1.0.1 from Beckhoff Automation GmbH & Co. KG are vulnerable to denial of service attacks. The attacker needs to send several specifically crafted requests to the running OPC UA server. After some of these requests the OPC UA server is no longer responsive to any client. This is without effect to the real-time functionality of IPCs.

Affected Software

3 affected components
Beckhoff IPC Diagnostics UA Server<=3.1.0.1
Beckhoff TF6100<=3.3.18
Beckhoff TwinCAT OPC UA Server<=2.3.0.12

Remediation

Information

For devices running Windows but not Windows CE or TwinCAT/BSD please get a recent version of the OPC UA servers through the conventional ways and update your system. For devices running Windows CE please request a recent image via Beckhoff’s support and apply it to your device. For the product CX8091 please use firmware version "CX8091_CE600_LF_v356f_TC211R3_B2306_v2" or later. Please note that the updated OPC UA server leaves less RAM available to your application on the CX8091.

Event History

May 13, 2021
CVE Published
via MITRE·01:45 PM
Data Sourced
via MITRE·01:45 PM
RemedyDescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2020-12526?

CVE-2020-12526 has a severity rating that indicates it can lead to denial of service attacks.

2

How do I fix CVE-2020-12526?

To fix CVE-2020-12526, update the TwinCAT OPC UA Server and IPC Diagnostics UA Server to their latest versions.

3

Which versions are affected by CVE-2020-12526?

CVE-2020-12526 affects TwinCAT OPC UA Server versions up to 2.3.0.12 and IPC Diagnostics UA Server versions up to 3.1.0.1.

4

What type of attack does CVE-2020-12526 enable?

CVE-2020-12526 enables attackers to perform denial of service attacks against the vulnerable OPC UA servers.

5

Who is affected by CVE-2020-12526?

Organizations using Beckhoff Automation OPC UA servers, specifically affected versions, are at risk from CVE-2020-12526.

Company

Resources

Contact

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