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PatchSiren cyber security CVE debrief

CVE-2024-42244 Siemens CVE debrief

A vulnerability in the Linux kernel's USB serial mos7840 driver can cause a system crash during resume operations. The issue stems from a change in the USB serial core that calls a generic resume implementation when the driver lacks one. For the mos7840 driver, which supports multiple read URBs, both port read URBs are submitted on resume for open ports, but the context pointer of the second URB remains set to the core rather than the mos7840 port structure, leading to a crash. This vulnerability was published on August 12, 2025, and last modified on February 25, 2026. CISA's advisory ICSA-25-226-07, republished based on Siemens ProductCERT SSA-355557, lists this CVE as affecting Siemens industrial networking products including RUGGEDCOM RST2428P and SCALANCE families, though the threat assessment categorizes the impact as 'Misinformed' for the listed product IDs.

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 running Linux-based industrial control systems, particularly those using Siemens RUGGEDCOM RST2428P, SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family, or SCALANCE XCM-/XRM-/XCH-/XRH-300 family devices. System administrators responsible for kernel maintenance on systems with USB serial devices should also prioritize this fix.

Technical summary

The mos7840 USB serial driver in the Linux kernel contains a flaw where the second port read URB's context pointer is not properly set to the mos7840 port structure during resume operations. When the USB serial core's generic resume implementation is invoked, both read URBs are submitted, but the incorrect context pointer causes a crash. This vulnerability affects systems using the mos7840 driver with multiple read URB support, including certain Siemens industrial networking products. The CVSS 3.1 score is 5.5 (MEDIUM).

Defensive priority

medium

Recommended defensive actions

  • Review CISA advisory ICSA-25-226-07 and Siemens ProductCERT SSA-355557 for updated affected product information and patch availability
  • Apply kernel updates from your Linux distribution that include the fix for CVE-2024-42244
  • For Siemens industrial products, consult Siemens ProductCERT for specific firmware updates addressing this vulnerability
  • Implement defense-in-depth strategies for industrial control systems per CISA recommended practices
  • Monitor systems for unexpected crashes or instability during USB device resume operations
  • Restrict physical access to USB ports on affected industrial systems where feasible

Evidence notes

The vulnerability description is drawn from the CVE record and CISA CSAF source. The affected product information and 'Misinformed' threat classification come from CISA advisory ICSA-25-226-07, which was republished on February 25, 2026 based on Siemens ProductCERT advisory SSA-355557. The CVSS score of 5.5 (MEDIUM) is taken from the official CVE record.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-42244 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-42244

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

  • CVE-2024-42244 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-42244

    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.