CVE-2019-6821

CWE-330: Use of Insufficiently Random Values vulnerability, which could cause the hijacking of the TCP connection when using Ethernet communication in Modicon M580 firmware versions prior to V2.30, and all firmware versions of Modicon M340, Modicon Premium, Modicon Quantum.

• CWE-330
• CWE-330

• http://www.securityfocus.com/bid/108366Third Party Advisory, VDB Entry
• https://ics-cert.us-cert.gov/advisories/ICSA-19-136-01Third Party Advisory, US Government Resource
• https://www.schneider-electric.com/en/download/document/SEVD-2019-134-03/Patch, Vendor Advisory
• http://www.securityfocus.com/bid/108366Third Party Advisory, VDB Entry
• https://ics-cert.us-cert.gov/advisories/ICSA-19-136-01Third Party Advisory, US Government Resource
• https://www.schneider-electric.com/en/download/document/SEVD-2019-134-03/Patch, Vendor Advisory

Published

May 22, 2019

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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