PatchSiren cyber security CVE debrief

CVE-2024-40904 Siemens CVE debrief

A vulnerability in the Linux kernel's USB CDC-WDM (Wireless Device Management) class driver can cause CPU lockup due to excessive log message generation. The issue stems from uncontrolled logging that can exhaust system resources, leading to denial of service conditions. This vulnerability affects Siemens industrial networking products running SINEC OS, specifically the RUGGEDCOM RST2428P and SCALANCE X-family switches. The CVSS 4.4 MEDIUM severity reflects local attack vector requirements and high availability impact. CISA published this advisory on August 12, 2025, with subsequent revisions through February 25, 2026, including corrections to affected product lists and clarification of impacted configurations.

Vendor: Siemens
Product: RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS: MEDIUM 4.4
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 infrastructure, particularly those deploying RUGGEDCOM RST2428P or SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family devices in critical infrastructure environments. OT security teams, ICS asset owners, and network administrators responsible for maintaining availability of industrial control systems should prioritize monitoring vendor guidance for remediation updates.

Technical summary

The vulnerability exists in the USB CDC-WDM class driver within the Linux kernel. Excessive log message generation can trigger CPU lockup, resulting in denial of service. This affects Siemens industrial networking products utilizing SINEC OS, including RUGGEDCOM RST2428P and select SCALANCE X-family switches. The issue requires local access to exploit and primarily impacts availability.

Defensive priority

medium

Recommended defensive actions

Review Siemens ProductCERT advisory SSA-355557 for detailed product-specific guidance and patch availability
Apply vendor-provided firmware updates for affected SCALANCE and RUGGEDCOM devices when available
Monitor system logs for anomalous USB CDC-WDM driver activity on affected industrial networking equipment
Implement network segmentation to limit exposure of industrial control system devices per CISA ICS recommended practices
Follow CISA guidance for defense-in-depth strategies for industrial control systems

Evidence notes

CVE published 2025-08-12 per CISA CSAF advisory ICSA-25-226-07. Advisory revised 2026-02-12 (corrected affected products), 2026-02-24 (clarified SCALANCE family configurations, removed rejected CVEs), and 2026-02-25 (CISA republication based on Siemens SSA-355557). Source indicates 'Misinformed' impact categorization for affected product IDs.

Official resources

2025-08-12