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PatchSiren cyber security CVE debrief

CVE-2024-35944 Siemens CVE debrief

A vulnerability in the VMCI (Virtual Machine Communication Interface) kernel module, specifically in the `dg_dispatch_as_host()` function, could allow a local attacker to trigger a memcpy run-time warning condition. The issue stems from improper memory handling during datagram dispatch operations in host mode. Successful exploitation could result in denial of service conditions on affected systems. The vulnerability has a CVSS 3.1 score of 5.5 (MEDIUM severity) with a local attack vector, low attack complexity, and low privileges required. No confidentiality or integrity impact is indicated, but availability impact is rated as high.

Vendor
Siemens
Product
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2023-12-12
Original CVE updated
2025-08-12
Advisory published
2023-12-12
Advisory updated
2025-08-12

Who should care

Organizations operating Siemens SIMATIC S7-1500 TM MFP industrial controllers with the GNU/Linux subsystem enabled should prioritize this vulnerability. System administrators responsible for OT/ICS environments, security teams managing industrial control systems, and personnel with interactive shell access to these devices are directly affected. Given the local attack vector, insider threats or compromised accounts with low privileges pose the primary risk.

Technical summary

The vulnerability exists in the VMCI (Virtual Machine Communication Interface) kernel module's `dg_dispatch_as_host()` function. The issue involves a memcpy() run-time warning that can be triggered, potentially leading to denial of service conditions. The VMCI module facilitates communication between virtual machines and the host system. The vulnerability is classified under CWE-787 (Out-of-bounds Write). The affected component is the GNU/Linux subsystem of the Siemens SIMATIC S7-1500 TM MFP, an industrial automation controller. No patch is currently available from the vendor.

Defensive priority

medium

Recommended defensive actions

  • Restrict interactive shell access to the GNU/Linux subsystem to trusted personnel only
  • Implement application whitelisting - only build and run applications from trusted sources
  • Monitor for anomalous process behavior or unexpected system crashes on affected devices
  • Apply vendor patches when Siemens releases a fix for this vulnerability
  • Segment industrial control networks to limit lateral movement opportunities
  • Review and implement CISA ICS recommended practices for defense in depth

Evidence notes

The vulnerability description indicates this is a VMCI kernel module issue in the `dg_dispatch_as_host()` function related to memcpy() operations. The CVSS vector (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) confirms local attack vector with high availability impact. The affected product is specifically the GNU/Linux subsystem of the Siemens SIMATIC S7-1500 TM MFP industrial controller.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-35944 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-35944

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2024-35944 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-35944

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source item URL

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2024/icsa-24-102-01.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-265688.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-265688.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-24-102-01

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-alerts/ics-alert-10-301-01

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/resources-tools/resources/ics-recommended-practices

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/topics/industrial-control-systems

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf

    Reference

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.