What’s Vulnerable › Vulnerabilities

CVE-2018-7856

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.6% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2019-05-22 · updated 2026-06-17
• Weakness: CWE-754

Description

A CWE-248: Uncaught Exception vulnerability exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum, and Modicon Premium which could cause a possible denial of Service when writing invalid memory blocks to the controller over Modbus.

Affected products

• Schneider-Electric Modicon M340 Firmware: before 3.10 — fixed in 3.10
• Schneider Electric SE Modicon M580: before 2.90 — fixed in 2.90
• Schneider-Electric Modicon Premium Firmware: all versions
• Modicon Quantum - all firmware versions: all versions

How to fix

Upgrade to a fixed version: Schneider-Electric Modicon M340 Firmware 3.10; Schneider Electric SE Modicon M580 2.90. Check the vendor advisory for mitigations.

References

• https://www.schneider-electric.com/en/download/document/SEVD-2019-134-11/
• https://www.talosintelligence.com/vulnerability_reports/TALOS-2019-0767
• https://www.schneider-electric.com/en/download/document/SEVD-2019-134-11/
• https://www.talosintelligence.com/vulnerability_reports/TALOS-2019-0767

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