CVE-2020-12526

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.

• CWE-20
• CWE-20

• https://cert.vde.com/en-us/advisories/vde-2020-051Third Party Advisory
• https://download.beckhoff.com/download/Document/product-security/Advisories/advisory-2021-001.pdfVendor Advisory
• https://cert.vde.com/en-us/advisories/vde-2020-051Third Party Advisory
• https://download.beckhoff.com/download/Document/product-security/Advisories/advisory-2021-001.pdfVendor Advisory

Published

May 13, 2021

Last Modified

Jun 17, 2026

Status

Modified

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