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Full vulnerability report · 2023
CVE-2021-22786High confidence

Schneider Electric Modicon M340 CPU (part numbers BMXP34*) — Exposure of Sensitive Information to an Unauthorized Actor

Schneider Electric · Modicon M340 CPU (part numbers BMXP34*)

7.5HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
SEVD-2022-221-04 · CSAF 2.0 · revision 5.0.0 · finalSchneider Electric CPCERTModicon PAC Controllers
6 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • Schneider Electric Modicon M340 CPU version 3.30 and prior
  • Schneider Electric Modicon M580 CPU version 3.22 and prior
  • Schneider Electric Modicon MC80 version 1.6 and prior
  • Schneider Electric Modicon MOMENTUM CPU version 2.3 and prior
  • Schneider Electric Legacy Modicon Quantum all versions
  • Schneider Electric Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) Versions prior to SV4.21
Summary
A CWE-200: Information Exposure vulnerability exists that could cause the exposure of sensitive information stored on the memory of the controller when communicating over the Modbus TCP protocol.
Remediation
Firmware V3.40 of Modicon includes a fix for this vulnerability and is available for download here: https://www.se.com/ww/en/download/document/BMXP34xxxxx_SV_xx.xx/
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-9921

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

A CWE-200: Information Exposure vulnerability exists that could cause the exposure of sensitive information stored on the memory of the controller when communicating over the Modbus TCP protocol. Affected Products: Modicon M340 CPU (part numbers BMXP34*) (Versions prior to V3.30), Modicon M580 CPU (part numbers BMEP* and BMEH*) (Versions prior to SV3.20), Modicon MC80 (BMKC80) (Versions prior to V1.6), Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) (All Versions), Modicon Momentum MDI (171CBU*) (Versions prior to V2.3), Legacy Modicon Quantum (All Versions)

What

A CWE-200: Information Exposure vulnerability exists that could cause the exposure of sensitive information stored on the memory of the controller when communicating over the Modbus TCP protocol. Affected Products: Modicon M340 CPU (part numbers BMXP34*) (Versions prior to V3.30), Modicon M580 CPU (part numbers BMEP* and BMEH*) (Versions prior to SV3.20), Modicon MC80 (BMKC80) (Versions prior to V1.6), Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) (All Versions), Modicon Momentum MDI (171CBU*) (Versions prior to V2.3), Legacy Modicon Quantum (All Versions)

Why

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may obtain information outside the intended access boundary.

What

A CWE-200: Information Exposure vulnerability exists that could cause the exposure of sensitive information stored on the memory of the controller when communicating over the Modbus TCP protocol. Affected Products: Modicon M340 CPU (part numbers BMXP34*) (Versions prior to V3.30), Modicon M580 CPU (part numbers BMEP* and BMEH*) (Versions prior to SV3.20), Modicon MC80 (BMKC80) (Versions prior to V1.6), Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) (All Versions), Modicon Momentum MDI (171CBU*) (Versions prior to V2.3), Legacy Modicon Quantum (All Versions)

Why

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may obtain information outside the intended access boundary.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Exposure of Sensitive Information to an Unauthorized Actor → obtain information outside the intended access boundary
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-200 ↗

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.INoneIntegrity impact: No direct loss is represented by this metric.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-200
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

CERT-FR · French · CERTFR-2022-AVI-717Multiples vulnérabilités dans les produits Schneider

rd?id=CVE-2019-6847 Référence CVE CVE-2020-12525 https://www.cve.org/CVERecord?id=CVE-2020-12525 Référence CVE CVE-2020-28895 https://www.cve.org/CVERecord?id=CVE-2020-28895 Référence CVE CVE-2020-35198 https://www.cve.org/CVERecord?id=CVE-2020-35198 Référence CVE CVE-2021-22778 https://www.cve.org/CVERecord?id=CVE-2021-22778 Référence CVE CVE-2021-22779 https://www.cve.org/CVERecord?id=CVE-2021-22779 Référence CVE CVE-2021-22780 https://www.cve.org/CVERecord?id=CVE-2021-22780 Référence CVE CVE-2021-22781 https://www.cve.org/CVERecord?id=CVE-2021-22781 Référence CVE CVE-2021-22782 https://www.cve.org/CVERecord?id=CVE-2021-22782 Référence CVE CVE-2021-22786 https://www.cve.org/CVERecord?id=CVE-2021-22786 Référence CVE CVE-2021-22789 https://www.cve.org/CVERecord?id=CVE-2021-22789 Référence CVE CVE-2021-22790 https://www.cve.org/CVERecord?id=CVE-2021-22790 Référence CVE CVE-2021-22791 https://www.cve.org/CVERecord?id=CVE-2021-22791 Référence CVE CVE-2021-22792 https://www.cve.org/CVERecord?id=CVE-2021-22792 Référence CVE CVE-2021-4104 https://www.cve.org/CVERecord?id=CVE-2021-4104 Référence CVE CVE-2021-44228 https://www.cve.org/CVERecord?id=CVE-2021-44228 Référence CVE CVE-2021-44832 https://www.cve.org/CVERecord?id=CVE-2021-44832 Référence CVE CVE-2021-45046 https://www.cve.org/CVERecord?id=CV

Official advisory
CERT-FR · French · CERTFR-2022-AVI-1093Multiples vulnérabilités dans les produits Schneider

rg/CVERecord?id=CVE-2019-6842 Référence CVE CVE-2019-6843 https://www.cve.org/CVERecord?id=CVE-2019-6843 Référence CVE CVE-2019-6844 https://www.cve.org/CVERecord?id=CVE-2019-6844 Référence CVE CVE-2019-6846 https://www.cve.org/CVERecord?id=CVE-2019-6846 Référence CVE CVE-2019-6847 https://www.cve.org/CVERecord?id=CVE-2019-6847 Référence CVE CVE-2020-28895 https://www.cve.org/CVERecord?id=CVE-2020-28895 Référence CVE CVE-2020-35198 https://www.cve.org/CVERecord?id=CVE-2020-35198 Référence CVE CVE-2020-6996 https://www.cve.org/CVERecord?id=CVE-2020-6996 Référence CVE CVE-2021-22779 https://www.cve.org/CVERecord?id=CVE-2021-22779 Référence CVE CVE-2021-22786 https://www.cve.org/CVERecord?id=CVE-2021-22786 Référence CVE CVE-2021-22789 https://www.cve.org/CVERecord?id=CVE-2021-22789 Référence CVE CVE-2021-22790 https://www.cve.org/CVERecord?id=CVE-2021-22790 Référence CVE CVE-2021-22791 https://www.cve.org/CVERecord?id=CVE-2021-22791 Référence CVE CVE-2021-22792 https://www.cve.org/CVERecord?id=CVE-2021-22792 Référence CVE CVE-2022-37300 https://www.cve.org/CVERecord?id=CVE-2022-37300 Référence CVE CVE-2022-37301 https://www.cve.org/CVERecord?id=CVE-2022-37301 Référence CVE CVE-2022-4062 https://www.cve.org/CVERecord?id=CVE-2022-4062 Référence CVE CVE-2022-42970 https://www.cve.org/CVERecord?id=CV

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Schneider Electric Modicon M340 CPU version 3.30 and prior; Schneider Electric Modicon M580 CPU version 3.22 and prior; Schneider Electric Modicon MC80 version 1.6 and prior; Schneider Electric Modicon MOMENTUM CPU version 2.3 and prior; Schneider Electric Legacy Modicon Quantum all versions; Schneider Electric Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) Versions prior to SV4.21
Fixed
Schneider Electric Modicon M340 CPU 3.40; Schneider Electric Modicon MC80 1.70; Schneider Electric Modicon MOMENTUM CPU SV2.4; Schneider Electric Modicon M580 CPU 4.10; Schneider Electric Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) Version SV4.21
Action
Firmware V3.40 of Modicon includes a fix for this vulnerability and is available for download here: https://www.se.com/ww/en/download/document/BMXP34xxxxx_SV_xx.xx/
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 1 Feb 2023 · Last source change 5 Feb 2025, 20:06 UTC · CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-9921
Product sourceVendor CSAF · Schneider Electric CPCERT
Remediation sourceVendor CSAF · Schneider Electric CPCERT
CWE sourceCNA
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-9921↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-22786 · cve.blacktree.nl