CVE-2019-6856

mediumpriority · track · 31EPSS 0.016 · 76 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.63% (76th) EPSS

CVSS 5 · medium

Is it mine?

43 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisa_csaf_ot · nvd

EPSS · scored 2026-10-27

A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists in Modicon M580, Modicon M340, Modicon Quantum, Modicon Premium (see security notification for specific versions) which could cause a Denial of Service when writing specific physical memory blocks using Modbus TCP.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedModicon M340cisa_csaf_ot
BMXP341000 and H: Modicon M340 firmware v3.20
https://www.schneider-electric.com/en/download/document/BMXP341000_Firmwares/
FixedModicon M580cisa_csaf_ot
BMXP341000 and H: Modicon M340 firmware v3.20
https://www.schneider-electric.com/en/download/document/BMXP341000_Firmwares/
FixedModicon Premiumcisa_csaf_ot
BMXP341000 and H: Modicon M340 firmware v3.20
https://www.schneider-electric.com/en/download/document/BMXP341000_Firmwares/
FixedModicon Quantumcisa_csaf_ot
BMXP341000 and H: Modicon M340 firmware v3.20
https://www.schneider-electric.com/en/download/document/BMXP341000_Firmwares/
MitigationModicon M340cisa_csaf_ot
140CPU65160S: Please contact Schneider Electric customer support to get the Quantum v3.60 firmware
MitigationModicon M580cisa_csaf_ot
140CPU65160S: Please contact Schneider Electric customer support to get the Quantum v3.60 firmware
MitigationModicon Premiumcisa_csaf_ot
140CPU65160S: Please contact Schneider Electric customer support to get the Quantum v3.60 firmware
MitigationModicon Quantumcisa_csaf_ot
140CPU65160S: Please contact Schneider Electric customer support to get the Quantum v3.60 firmware

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-754USprimaryCWE-754US

affected products (43)

Products and version ranges known to be affected.

Modicon M340: all versions prior to v3.01all versionscisa_csaf_otUS
Modicon M580: all versions prior to v2.80all versionscisa_csaf_otUS
Modicon Premium: all versions prior to v3.20all versionscisa_csaf_otUS
Modicon Quantum: all versions prior to v3.52all versionscisa_csaf_otUS
Modicon Quantum: all versions prior to v3.60all versionscisa_csaf_otUS
Schneider Electric Software, LLC Modicon M340< 3.01cisa_csaf_otUS
Schneider Electric Software, LLC Modicon M580< 2.80cisa_csaf_otUS
Schneider Electric Software, LLC Modicon Premium< 3.20cisa_csaf_otUS
Schneider Electric Software, LLC Modicon Quantum< 3.52cisa_csaf_otUS
Schneider Electric Software, LLC Modicon Quantum< 3.60cisa_csaf_otUS
Schneider Electric SE Modicon M580, Modicon M340, Modicon Quantum, Modicon Premium (see security notification for specific versions)≤ Modicon M580enisa_euvdEU
Schneider Electric SE Modicon M580, Modicon M340, Modicon Quantum, Modicon Premium (see security notification for specific versions)≤ Modicon Quantumenisa_euvdEU
Schneider Electric SE Modicon M580, Modicon M340, Modicon Quantum, Modicon Premium (see security notification for specific versions)≤ Modicon M340enisa_euvdEU
Schneider Electric SE Modicon M580, Modicon M340, Modicon Quantum, Modicon Premium (see security notification for specific versions)≤ Modicon Premium (see security notification for specific versions)enisa_euvdEU
schneider-electric 140cpu65150 firmware< 3.52nvdUScpe:2.3:o:schneider-electric:140cpu65150_firmware:*:*:*:*:*:*:*:*
schneider-electric 140cpu65160 firmware< 3.52nvdUScpe:2.3:o:schneider-electric:140cpu65160_firmware:*:*:*:*:*:*:*:*
schneider-electric 140cpu65160s firmware< 3.52nvdUScpe:2.3:o:schneider-electric:140cpu65160s_firmware:*:*:*:*:*:*:*:*
schneider-electric 140cpu65260 firmware< 3.52nvdUScpe:2.3:o:schneider-electric:140cpu65260_firmware:*:*:*:*:*:*:*:*
schneider-electric 140cpu65860 firmware< 3.52nvdUScpe:2.3:o:schneider-electric:140cpu65860_firmware:*:*:*:*:*:*:*:*
schneider-electric 140cpu67060 firmware< 3.52nvdUScpe:2.3:o:schneider-electric:140cpu67060_firmware:*:*:*:*:*:*:*:*

showing 20 of 43

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-20-016-01Schneider Electric Modicon Controllers (Update A)2020-01-16icsa · cisa_csaf_otUS
Successful exploitation of this vulnerability could result in a denial-of-service condition.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cisa_csaf_ot nvd NVD CVE.org MITRE

published 2020-01-06modified 2026-06-17

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references (10)

External citations — patches, advisories, analysis.

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