PatchSiren cyber security CVE debrief

CVE-2024-49878 Siemens CVE debrief

A vulnerability in the Linux kernel's CXL (Compute Express Link) memory driver affects Siemens industrial networking products running SINEC OS. The flaw stems from improper resource hierarchy handling in drivers/dax/kmem.c, where add_memory_driver_managed() creates a nested resource structure during CXL memory onlining. This causes region_intersects() to fail when locating System RAM resources, as it expects these resources at the top level of iomem_resource rather than as descendants of CXL Window resources. The vulnerability can lead to denial of service conditions on affected systems. Siemens has released firmware updates to address this issue in affected RUGGEDCOM and SCALANCE product families.

Vendor: Siemens
Product: RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS: MEDIUM 5.5
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 RUGGEDCOM RST2428P, SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500, or SCALANCE XCM-/XRM-/XCH-/XRH-300 family industrial networking devices in critical infrastructure environments, particularly those utilizing CXL memory expansion capabilities.

Technical summary

The vulnerability exists in the Linux kernel's DAX kmem driver (drivers/dax/kmem.c), which is used when onlining CXL memory. The function add_memory_driver_managed() creates a resource hierarchy where 'System RAM (kmem)' becomes a child of 'CXL Window X' rather than a direct child of iomem_resource. This violates assumptions in region_intersects(), which expects all System RAM resources to be at the top level of the resource tree. The mismatch can cause memory region intersection checks to fail, potentially leading to system instability or denial of service. The flaw is classified as CWE-20 (Improper Input Validation) and carries a CVSS 3.1 score of 5.5 (Medium severity) with local attack vector, low attack complexity, and high availability impact.

Defensive priority

medium

Recommended defensive actions

Apply vendor-provided firmware updates to V3.2 or later for affected RUGGEDCOM RST2428P and SCALANCE XCM-/XRM-/XCH-/XRH-300 family devices
For SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family devices, consult Siemens ProductCERT advisory SSA-355557 for specific configuration guidance and update instructions
Implement network segmentation for industrial control systems to limit exposure of affected devices
Monitor Siemens ProductCERT security advisories for additional updates or clarifications
Follow CISA ICS recommended practices for defense-in-depth strategies in industrial control environments

Evidence notes

Vulnerability description and affected product information sourced from CISA CSAF advisory ICSA-25-226-07, which references Siemens ProductCERT advisory SSA-355557. CVSS 3.1 vector confirms local attack vector with low attack complexity and high availability impact.

Sources and references

Verified primary and authoritative sources

CVE-2024-49878 CVE Program record
Publisher, destination, and source semantics verified

URL: https://www.cve.org/CVERecord?id=CVE-2024-49878

CVE Program - Official CVE Program record with source-provided CVE metadata.
CVE-2024-49878 NVD vulnerability detail
Publisher, destination, and source semantics verified

URL: https://nvd.nist.gov/vuln/detail/CVE-2024-49878

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-25-226-07.json

cisa_csaf
Source reference
Unverified legacy reference

URL: https://cert-portal.siemens.com/productcert/csaf/ssa-355557.json

Reference
Source reference
Unverified legacy reference

URL: https://cert-portal.siemens.com/productcert/html/ssa-355557.html

Reference
Source reference
Unverified legacy reference

URL: https://www.cisa.gov/news-events/ics-advisories/icsa-25-226-07

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.