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Full vulnerability report · 2021
CVE-2021-30188High confidence

CODESYS V2 runtime system SP before 2.4.7.55 has a Stack-based Buffer Overflow

n/a · n/a

9.8CriticalCVSS 3.1
Recommended action
Within 72 hours

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

Mitigation 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-2021-222-06 · CSAF 2.0 · revision 1.0.0 · finalSchneider Electric CPCERTCODESYS V2 Vulnerabilities in Programmable Automation Controller (PacDrive) M
1 known affected

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

  • Schneider Electric Programmable Automation Controller (PacDrive) M All versions
Summary
A crafted request may cause a stack-based buffer overflow in the affected CODESYS products, resulting in a denial-of-service condition or being utilized for remote code execution.
Remediation
The Programmable Automation Controller (PacDrive) M product has been replaced with the newer PacDrive 3 product. Customers should consider migrating to the PacDrive 3 and following the steps below to resolve these issues: 1. Migrate to PacDrive 3 controllers: https://www.se.com/ww/en/product-range/7590-pacdrive-3/?subNodeId=12367561635en_WW. Please contact your local Schneider Electric technical support for more information. 2. Download and install latest EcoStruxure Machine Expert software available here: https://www.se.com/ww/en/product-range/2226-ecostruxure-machine-expert-%28somachine%29/ to program PacDrive 3 controllers. 3. Upgrade to the latest firmware versions of PacDrive 3 controllers through Schneider Electric Software Update (SESU) Note: a reboot of the controller will be required.
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-2021-17120

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.

Mitigation available
01

What, why and how

CODESYS V2 runtime system SP before 2.4.7.55 has a Stack-based Buffer Overflow.

What

CODESYS V2 runtime system SP before 2.4.7.55 has a Stack-based Buffer Overflow.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

CODESYS V2 runtime system SP before 2.4.7.55 has a Stack-based Buffer Overflow.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

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 → Out-of-bounds Write → cause the confidentiality, integrity or availability impact described by the vendor
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-787 ↗

CWE-787: Out-of-bounds Write. The product writes data past the end, or before the beginning, of the intended buffer.

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:H/A:H

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.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
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-787
A

Official authority intelligence

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

CERT-FR · French · CERTFR-2021-AVI-622Multiples vulnérabilités dans les produits Schneider Electric

d?id=CVE-2021-21830 Référence CVE CVE-2021-22704 https://www.cve.org/CVERecord?id=CVE-2021-22704 Référence CVE CVE-2021-22775 https://www.cve.org/CVERecord?id=CVE-2021-22775 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-2021-22793 https://www.cve.org/CVERecord?id=CVE-2021-22793 Référence CVE CVE-2021-30186 https://www.cve.org/CVERecord?id=CVE-2021-30186 Référence CVE CVE-2021-30188 https://www.cve.org/CVERecord?id=CVE-2021-30188 Référence CVE CVE-2021-30195 https://www.cve.org/CVERecord?id=CVE-2021-30195 Référence CVE CVE-2021-31166 https://www.cve.org/CVERecord?id=CVE-2021-31166 Référence CVE CVE-2021-34527 https://www.cve.org/CVERecord?id=CVE-2021-34527 Gestion détaillée du document le 12 août 2021 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des sy

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.
Mitigation available
Affected
Schneider Electric Programmable Automation Controller (PacDrive) M All versions
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
The Programmable Automation Controller (PacDrive) M product has been replaced with the newer PacDrive 3 product. Customers should consider migrating to the PacDrive 3 and following the steps below to resolve these issues: 1. Migrate to PacDrive 3 controllers: https://www.se.com/ww/en/product-range/7590-pacdrive-3/?subNodeId=12367561635en_WW. Please contact your local Schneider Electric technical support for more information. 2. Download and install latest EcoStruxure Machine Expert software available here: https://www.se.com/ww/en/product-range/2226-ecostruxure-machine-expert-%28somachine%29/ to program PacDrive 3 controllers. 3. Upgrade to the latest firmware versions of PacDrive 3 controllers through Schneider Electric Software Update (SESU) Note: a reboot of the controller will be required.
04

Evidence and provenance

Published 25 May 2021 · Last source change 3 Aug 2024, 22:24 UTC · CWE-787 · Out-of-bounds Write

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
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-2021-17120
Product sourceVendor CSAF · Schneider Electric CPCERT
Remediation sourceVendor CSAF · Schneider Electric CPCERT
CWE sourceNIST NVD
NVD statusNVD enriched

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-2021-17120↗Vendor CSAF · Schneider Electric CPCERT↗CVE authority or vendor reference↗Vendor advisory↗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-2021-30188 · cve.blacktree.nl