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CVE-2024-39475 Siemens CVE debrief

CVE-2024-39475 is a divide-by-zero vulnerability in the Linux kernel's S3 Savage framebuffer driver (savagefb). The issue stems from incomplete error handling: while commit 04e5eac8f3ab added a check to prevent pixclock=0 from causing division by zero in savagefb_check_var(), the savagefb_probe() function failed to propagate this error condition. When a zero pixclock value is supplied, the unchecked error path allows the divide-by-zero to occur. Siemens has identified this vulnerability as affecting SINEC OS-based industrial networking products including the RUGGEDCOM RST2428P and SCALANCE X-family switches. The vendor has rated this vulnerability as having no security impact (CVSS 0.0) for affected products, with one product family explicitly marked as 'Misinformed' (not actually vulnerable). A vendor fix is available requiring update to SINEC OS V3.1 or later.

Vendor
Siemens
Product
RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS
NONE
CISA KEV
Not listed in stored evidence
Original CVE published
2025-08-12
Original CVE updated
2026-02-25
Advisory published
2025-08-12
Advisory updated
2026-02-25

Who should care

Organizations operating Siemens industrial networking equipment with SINEC OS, particularly RUGGEDCOM and SCALANCE product lines in industrial control system (ICS/OT) environments. Security teams responsible for Linux kernel security in embedded framebuffer applications.

Technical summary

The savagefb driver in the Linux kernel contains a divide-by-zero vulnerability. A prior commit (04e5eac8f3ab) added validation in savagefb_check_var() to reject pixclock=0, but savagefb_probe() does not check the return value. This omission allows the error condition to propagate, resulting in division by zero when pixclock is zero. The vulnerability affects the S3 Savage framebuffer implementation used in some embedded/industrial systems.

Defensive priority

low

Recommended defensive actions

  • Review SINEC OS version on affected Siemens industrial networking products (RUGGEDCOM RST2428P, SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family)
  • Update affected devices to SINEC OS V3.1 or later per vendor guidance
  • Verify SCALANCE XCM-/XRM-/XCH-/XRH-300 family devices are not affected (marked as 'Misinformed' in vendor advisory)
  • Apply standard ICS defense-in-depth practices for industrial control systems per CISA guidance

Evidence notes

The vulnerability description is sourced from CISA CSAF advisory ICSA-25-226-15, which republishes Siemens ProductCERT advisory SSA-613116. The technical root cause is documented in the Linux kernel commit history. Siemens' assessment that this vulnerability has no security impact for their products is explicitly noted in the CSAF threat data.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-39475 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-39475

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

  • CVE-2024-39475 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-39475

    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/2025/icsa-25-226-15.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-613116.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-613116.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-25-226-15

    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.