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Resource Allocation Without LimitsWeakness · CWE-770

CVE-2026-54429

HIGH · 7.4 CVSS v3.1 Published 2026-07-14
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
79/100
Remediation priority · High
No privileges Zero-click 5 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability has been identified in SIMATIC S7-PLCSIM Advanced (All versions). Affected devices do not properly handle high-volume multicast network traffic, which can exhaust available memory resources in the affected application. This could allow an unauthenticated attacker on the local network segment to cause a denial-of-service condition of the affected application. The affected application becomes inaccessible and requires a manual restart; no project data is lost. Successful exploitation requires a specific project configuration to be already active on the targeted instance.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

SIMATIC S7-PLCSIM Advanced fails to properly handle high-volume multicast network traffic, causing memory resource exhaustion. An unauthenticated attacker on the local network segment can send specially crafted multicast traffic to trigger a denial-of-service condition, rendering the application inaccessible until manual restart. Exploitation requires a specific project configuration to be active on the target instance.

MitigationApply vendor patches when available; meanwhile, implement network segmentation to restrict local network access and monitor for anomalous multicast traffic patterns on the industrial network segment.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify SIMATIC S7-PLCSIM Advanced installation and version
    Open Windows Control Panel > Programs and Features, locate SIMATIC S7-PLCSIM Advanced in the list, and note the installed version. Alternatively, right-click the application executable in its installation directory (typically under C:\Program Files\Siemens\) and view Properties > Details to find the File Version.
    Affected if The installed version matches any version of SIMATIC S7-PLCSIM Advanced that has not yet received the vendor patch for this vulnerability.
  2. Confirm whether a project configuration is loaded and active
    Launch SIMATIC S7-PLCSIM Advanced and examine the runtime interface or project explorer panel. Look for an active project configuration currently loaded in the simulation environment. Check if the PLCSIM Advanced runtime shows a loaded project as opposed to an empty or idle state.
    Affected if A specific project configuration is actively loaded in the PLCSIM Advanced instance, which is required for the vulnerability to be exploitable.
  3. Monitor network interface for anomalous multicast traffic
    Use a network capture tool such as Wireshark or Microsoft Network Monitor to capture traffic on the active network interface. Apply a filter for multicast traffic (e.g., multicast IP ranges like 224.0.0.0/4 or IGMP traffic). Observe the volume and frequency of incoming multicast packets over a period of several minutes.
    Affected if High-volume or unusually frequent multicast traffic is being received on the network segment where the PLCSIM Advanced instance is operating.
  4. Check for memory resource exhaustion on the host system
    Open Windows Task Manager, go to the Processes or Details tab, and locate the PLCSIM Advanced executable (typically S7ProSim.exe or similar). Monitor the Memory (Private Working Set) column for continuously increasing memory usage. Also check if the application becomes unresponsive or exhibits extremely high memory consumption.
    Affected if The PLCSIM Advanced process exhibits steadily increasing memory consumption or consumes excessive system memory, indicating the vulnerability may be triggered.

A user is affected if SIMATIC S7-PLCSIM Advanced is running with an active project configuration and the host system is receiving high-volume multicast traffic that causes the application to become unresponsive due to memory exhaustion.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply vendor patches when available; meanwhile, implement network segmentation to restrict local network access and monitor for anomalous multicast traffic patterns on the industrial network segment.

Have this fixed Scoped from the published advisory
  • Consultation8.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,940
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-54429 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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