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Fencer Vulns
critical 9.8

CVE-2018-7847 json

A CWE-284: Improper Access Control vulnerability exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum, and Modicon Pre…

published 2019-05-22 7 y ago modified 2026-06-17 4 mo ago also EUVD-2018-19559

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
3.8%
EPSS 3.8% chance of exploitation in 30 days, percentile 90%
public exploits
0
none known

Summary

A CWE-284: Improper Access Control vulnerability exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum, and Modicon Premium which could cause denial of service or potential code execution by overwriting configuration settings of the controller over Modbus.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-25-114-01 updated cvss 9.8

Schneider Electric Modicon Controllers (Update A)

  • Schneider Electric Modicon M340 Controller Modicon M340 Firmware < 3.10
    affected: vendor fix, mitigation se.com
  • Schneider Electric Modicon M580 Controller Modicon M580 Firmware < 2.90
    affected: vendor fix, mitigation se.com
  • Schneider Electric Modicon Premium Controller Modicon Premium Firmware all versions
    affected: mitigation, no fix planned se.com
  • Schneider Electric Modicon Quantum Controller Modicon Quantum Firmware all versions Schneider Electric Modicon Quantum Safety Controller Modicon Quantum Safety Firmware all versions
    affected: mitigation, no fix planned se.com
  • Schneider Electric Modicon M340 Controller Modicon M340 Firmware 3.60 Schneider Electric Modicon M580 Controller Modicon M580 Firmware 4.20
    fixed

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

Exploit prediction

3.81% chance of exploitation in the next 30 days, higher than 90% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • talosintelligence.com https://www.talosintelligence.com/vulnerability_reports/TALOS-2018-0742 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

  • n/a Modicon M580 Modicon M340 Modicon Quantum Modicon Premium

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.