What’s Vulnerable › Vulnerabilities

CVE-2021-40142

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-08-27 · updated 2026-06-17
• Weakness: CWE-119

Description

In OPC Foundation Local Discovery Server (LDS) before 1.04.402.463, remote attackers can cause a denial of service (DoS) by sending carefully crafted messages that lead to Access of a Memory Location After the End of a Buffer.

Affected products

• Opcfoundation Local Discover Server: before 1.04.402.463 — fixed in 1.04.402.463
• Siemens Simatic Net Pc: 14, 15, 16, 17
• Siemens Simatic Process Historian Opc Ua Server Firmware: before 2022; 2022 — fixed in 2022
• Siemens Simatic Wincc: all versions
• Siemens Simatic Wincc Runtime: all versions
• Siemens Simatic Wincc Unified Scada Runtime: all versions
• Siemens TeleControl Server Basic: 3.0

How to fix

Upgrade to a fixed version: Opcfoundation Local Discover Server 1.04.402.463; Siemens Simatic Process Historian Opc Ua Server Firmware 2022. Check the vendor advisory for mitigations.

References

• https://cert-portal.siemens.com/productcert/pdf/ssa-321292.pdf
• https://files.opcfoundation.org/SecurityBulletins/OPC%20Foundation%20Security%20Bulletin%20CVE-2021-40142.pdf
• https://opcfoundation.org/security-bulletins/
• https://cert-portal.siemens.com/productcert/pdf/ssa-321292.pdf
• https://files.opcfoundation.org/SecurityBulletins/OPC%20Foundation%20Security%20Bulletin%20CVE-2021-40142.pdf
• https://opcfoundation.org/security-bulletins/

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