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Full vulnerability report · 2024
CVE-2024-8938High confidence

Schneider Electric Modicon M340 CPU (part numbers BMXP34*) — Improper Restriction of Operations within the Bounds of a Memory Buffer

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

9.2CriticalCVSS 4.0
Recommended action
Within 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

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-2024-317-03 · CSAF 2.0 · revision 3.0.0 · finalSchneider Electric CPCERTModicon Controllers M340 / Momentum / MC80
3 known affected

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

  • Modicon M340 CPU Firmware Versions prior to SV3.65 installed on Modicon M340 CPU Controller (part numbers BMXP34*)
  • Modicon MC80 Firmware Versions prior to SV2.1 installed on Modicon MC80 Controller (part numbers BMKC80)
  • Modicon Momentum Unity M1E Processor Firmware Versions prior to SV2.80 installed on Modicon Momentum Unity M1E Processor Controller (171CBU*)
Summary
CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability exists that could cause potential arbitrary code execution after a successful Man-In -The Middle attack followed by sending crafted Modbus command in order to tamper with a function call used to evaluate memory size.
Remediation
Version SV3.65 of Modicon M340 firmware includes a fix for these vulnerabilities and is available for download here: https://www.se.com/ww/en/product-range/1468- modicon-m340
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-2024-49496

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 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

Patch available
01

What, why and how

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability exists that could cause a potential arbitrary code execution after a successful Man-In-The-Middle attack followed by sending a crafted Modbus function call to tamper with memory area involved in memory size computation.

What

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability exists that could cause a potential arbitrary code execution after a successful Man-In-The-Middle attack followed by sending a crafted Modbus function call to tamper with memory area involved in memory size computation.

Why

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.

What

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability exists that could cause a potential arbitrary code execution after a successful Man-In-The-Middle attack followed by sending a crafted Modbus function call to tamper with memory area involved in memory size computation.

Why

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.

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 → Improper Restriction of Operations within the Bounds of a Memory Buffer → execute code or commands in the affected security context
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-119 ↗

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer. The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.
Post-exploitation / living off the land
After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.
NetworkUnauthenticatedRemote code executionCWE-119
A

Official authority intelligence

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

CERT-FR · French · CERTFR-2024-AVI-0961Multiples vulnérabilités dans les produits Schneider Electric

De multiples vulnérabilités ont été découvertes dans les produits Schneider Electric. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

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
Modicon M340 CPU Firmware Versions prior to SV3.65 installed on Modicon M340 CPU Controller (part numbers BMXP34*); Modicon MC80 Firmware Versions prior to SV2.1 installed on Modicon MC80 Controller (part numbers BMKC80); Modicon Momentum Unity M1E Processor Firmware Versions prior to SV2.80 installed on Modicon Momentum Unity M1E Processor Controller (171CBU*)
Fixed
Modicon M340 CPU Firmware SV3.65 installed on Modicon M340 CPU Controller (part numbers BMXP34*); Modicon MC80 Firmware Version SV2.1 installed on Modicon MC80 Controller (part numbers BMKC80); Modicon Momentum Unity M1E Processor Firmware Version SV2.80 installed on Modicon Momentum Unity M1E Processor Controller (171CBU*)
Action
Version SV3.65 of Modicon M340 firmware includes a fix for these vulnerabilities and is available for download here: https://www.se.com/ww/en/product-range/1468- modicon-m340
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 13 Nov 2024 · Last source change 13 Nov 2024, 15:26 UTC · CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer

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-2024-49496
Product sourceVendor CSAF · Schneider Electric CPCERT
Remediation sourceVendor CSAF · Schneider Electric CPCERT
CWE sourceCNA
NVD statusNVD not scheduled

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
ENISA EUVD · EUVD-2024-49496↗Vendor CSAF · Schneider Electric CPCERT↗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-2024-8938 · cve.blacktree.nl