CVE-2020-7538

mediumpriority · track · 30EPSS 0.013 · 70 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.29% (70th) EPSS

CVSS 5 · medium

Is it mine?

7 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-28

A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists in PLC Simulator on EcoStruxureª Control Expert (now Unity Pro) (all versions) that could cause a crash of the PLC simulator present in EcoStruxureª Control Expert software when receiving a specially crafted request over Modbus.

remediations

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

A vendor fix is available.

FixedPLC Simulator for EcoStruxure Control Expertcisa_csaf_ot
Harden the engineering workstation running PLC Simulator for EcoStruxure Control Expert
FixedPLC Simulator for Unity Pro (former name of EcoStruxure Control Expert)cisa_csaf_ot
Harden the engineering workstation running PLC Simulator for EcoStruxure Control Expert
MitigationPLC Simulator for EcoStruxure Control Expertcisa_csaf_ot
If users choose not to apply the remediation provided above, they should immediately apply the following mitigations to reduce the risk of exploit:
MitigationPLC Simulator for Unity Pro (former name of EcoStruxure Control Expert)cisa_csaf_ot
If users choose not to apply the remediation provided above, they should immediately apply the following mitigations to reduce the risk of exploit:

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

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

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)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-754USCWE-754USCWE-754US

affected products (7)

Products and version ranges known to be affected.

PLC Simulator for EcoStruxure Control Expert: all versionsall versionscisa_csaf_otUS
PLC Simulator for Unity Pro (former name of EcoStruxure Control Expert): all versionsall versionscisa_csaf_otUS
Schneider Electric Software, LLC PLC Simulator for EcoStruxure Control Expertall versionscisa_csaf_otUS
Schneider Electric Software, LLC PLC Simulator for Unity Pro (former name of EcoStruxure Control Expert)all versionscisa_csaf_otUS
n/a PLC Simulator on EcoStruxureª Control Expert (now Unity Pro) (all versions)≤ PLC Simulator on EcoStruxureª Control Expert (now Unity Pro) (all versions)enisa_euvdEU
Schneider Electric EcoStruxure Control Expertall versionsfstec_bduRU
schneider-electric ecostruxure control expertall versionsnvdUScpe:2.3:a:schneider-electric:ecostruxure_control_expert:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-20-315-03Schneider Electric PLC Simulator for EcoStruxure Control Expert2020-11-10icsa · cisa_csaf_otUS
Successful exploitation of this vulnerability could cause a denial-of-service condition, which could result in a failure of the EcoStruxture Control Expert Simulator.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisa_csaf_ot nvd NVD CVE.org MITRE

published 2020-11-19modified 2026-06-17

references (6)

External citations — patches, advisories, analysis.

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