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CVE-2024-38635 Siemens CVE debrief

CVE-2024-38635 is a medium-severity vulnerability (CVSS 5.5) in the Linux kernel's SoundWire Cadence driver, affecting the Siemens SIMATIC S7-1500 TM MFP industrial control system's GNU/Linux subsystem. The flaw involves an invalid PDI (Peripheral Device Interface) offset that can trigger a denial-of-service condition. Published on April 9, 2024, and last modified on May 14, 2026, this vulnerability requires local access with low privileges to exploit, resulting in high availability impact but no confidentiality or integrity compromise. The vulnerability stems from improper input validation (CWE-20) in the soundwire subsystem's cadence driver implementation. Siemens has confirmed that no patch is currently available, making this a persistent exposure for affected industrial deployments. The advisory has undergone ten revision cycles through September 2025, indicating ongoing monitoring and cumulative CVE additions to the same product security notice.

Vendor
Siemens
Product
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2024-06-21
Original CVE updated
2026-08-04
Advisory published
2024-06-21
Advisory updated
2026-08-04

Who should care

Industrial control system operators, OT security teams, Siemens SIMATIC S7-1500 TM MFP administrators, manufacturing security engineers, and organizations running GNU/Linux subsystems on Siemens PLCs in production environments.

Technical summary

The vulnerability exists in the SoundWire Cadence driver within the Linux kernel, specifically in handling PDI (Peripheral Device Interface) offsets. An invalid offset value can cause the driver to malfunction, resulting in system instability or crash. The attack requires local access with authenticated low-privilege credentials. The CVSS 3.1 vector (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) confirms this is a local attack with no network exposure, requiring no user interaction, and impacting only availability. The affected product is the GNU/Linux subsystem component of Siemens SIMATIC S7-1500 TM MFP programmable logic controllers used in industrial automation environments.

Defensive priority

medium

Recommended defensive actions

  • Restrict interactive shell access to the GNU/Linux subsystem to trusted personnel only
  • Implement application whitelisting to ensure only trusted sources are built and executed
  • Monitor for anomalous local activity on affected Siemens SIMATIC S7-1500 TM MFP systems
  • Apply defense-in-depth strategies per ICS-CERT recommended practices until a patch becomes available
  • Review and enforce least-privilege access controls for local users on affected systems

Evidence notes

Source: CISA CSAF advisory ICSA-24-102-01; vendor confirmation via Siemens CERT portal SSA-265688; CVSS vector AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H indicates local attack vector with low attack complexity and low privileges required, resulting in high availability impact only. CWE-20 (Improper Input Validation) classification per source references. No fix available status confirmed in remediation section.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-38635 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-38635

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

  • CVE-2024-38635 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-38635

    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.