BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2021
CVE-2021-25671High confidence

A vulnerability has been identified in RWG1.M12 (All versions < V1.16.16), RWG1.M12D (All versions < V1.16.16), RWG1.M8 (All versions < V1.16.16)

Siemens · RWG1.M12

4.3MediumCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 3 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.38% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Siemens RWG1.M12 and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 3 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

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
SSA-448291 · CSAF 2.0 · revision 1 · finalSiemens ProductCERTSSA-448291: Denial-of-Service Vulnerability in ARP Protocol of RWG Universal Controllers
3 known affected

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

  • RWG1.M8
  • RWG1.M12
  • RWG1.M12D
Summary
Sending specially crafted ARP packets to an affected device could cause a partial denial-of-service, preventing the device to operate normally. A restart is needed to restore normal operations.
Remediation
Login to the RWG Controller Graphical programming platform, generate a new project file and download the new project file to the device
Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

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-2021-12563

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 actionPatch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 3 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

A vulnerability has been identified in RWG1.M12 (All versions < V1.16.16), RWG1.M12D (All versions < V1.16.16), RWG1.M8 (All versions < V1.16.16). Sending specially crafted ARP packets to an affected device could cause a partial denial-of-service, preventing the device to operate normally. A restart is needed to restore normal operations.

What

A vulnerability has been identified in RWG1.M12 (All versions < V1.16.16), RWG1.M12D (All versions < V1.16.16), RWG1.M8 (All versions < V1.16.16). Sending specially crafted ARP packets to an affected device could cause a partial denial-of-service, preventing the device to operate normally. A restart is needed to restore normal operations.

Why

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

How

An attacker operating through the affected interface 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

A vulnerability has been identified in RWG1.M12 (All versions < V1.16.16), RWG1.M12D (All versions < V1.16.16), RWG1.M8 (All versions < V1.16.16). Sending specially crafted ARP packets to an affected device could cause a partial denial-of-service, preventing the device to operate normally. A restart is needed to restore normal operations.

Why

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

How

An attacker operating through the affected interface 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
the affected interface → Allocation of Resources Without Limits or Throttling → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Unspecified
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-770 ↗

CWE-770: Allocation of Resources Without Limits or Throttling. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

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

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

AVAdjacentAttack vector: The attacker must be on an adjacent or logically close 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.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.ALowAvailability impact: A successful attack can cause a limited 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.
UnauthenticatedCWE-770
A

Official authority intelligence

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

Cyber Security Agency of Singapore · English · CSA-SB-20210714Security Bulletin 14 Jul 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 14 Jul 2021, published on 14 July 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-518Multiples vulnérabilités dans les produits Siemens

emens ssa-941426 du 13 juillet 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-941426.pdf Référence CVE CVE-2015-8011 https://www.cve.org/CVERecord?id=CVE-2015-8011 Référence CVE CVE-2020-15782 https://www.cve.org/CVERecord?id=CVE-2020-15782 Référence CVE CVE-2020-26147 https://www.cve.org/CVERecord?id=CVE-2020-26147 Référence CVE CVE-2020-27827 https://www.cve.org/CVERecord?id=CVE-2020-27827 Référence CVE CVE-2020-28400 https://www.cve.org/CVERecord?id=CVE-2020-28400 Référence CVE CVE-2021-20093 https://www.cve.org/CVERecord?id=CVE-2021-20093 Référence CVE CVE-2021-20094 https://www.cve.org/CVERecord?id=CVE-2021-20094 Référence CVE CVE-2021-25671 https://www.cve.org/CVERecord?id=CVE-2021-25671 Référence CVE CVE-2021-29998 https://www.cve.org/CVERecord?id=CVE-2021-29998 Référence CVE CVE-2021-31892 https://www.cve.org/CVERecord?id=CVE-2021-31892 Référence CVE CVE-2021-31893 https://www.cve.org/CVERecord?id=CVE-2021-31893 Référence CVE CVE-2021-31894 https://www.cve.org/CVERecord?id=CVE-2021-31894 Référence CVE CVE-2021-31895 https://www.cve.org/CVERecord?id=CVE-2021-31895 Référence CVE CVE-2021-33709 https://www.cve.org/CVERecord?id=CVE-2021-33709 Référence CVE CVE-2021-33710 https://www.cve.org/CVERecord?id=CVE-2021-33710 Référence CVE CVE-2021-33711 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-011959複数のシーメンス製品における制限またはスロットリング無しのリソースの割り当てに関する脆弱性

RWG1.M12、RWG1.M12D、RWG1.M8 には、制限またはスロットリング無しのリソースの割り当てに関する脆弱性が存在します。

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.
Fix availability varies by product
Affected
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 13 Jul 2021 · Last source change 3 Aug 2024, 20:11 UTC · CWE-770 · Allocation of Resources Without Limits or Throttling

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-2021-12563
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
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 ↗
  1. Remediation statusRemediation status changed from Patch available to Mitigation available.
    Before
    Patch available
    After
    Mitigation available
    Siemens ProductCERT ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
Remediation guidance recorded
ENISA EUVD · EUVD-2021-12563↗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-2021-25671 · cve.blacktree.nl