PatchSiren cyber security CVE debrief

CVE-2024-40929 Siemens CVE debrief

CVE-2024-40929 is an out-of-bounds access vulnerability in the Intel Wireless WiFi (iwlwifi) driver for Linux, specifically in the mac80211 virtual monitor (mvm) component. The flaw occurs when the driver accesses the ssids pointer without first validating that n_ssids is non-zero. In certain versions of cfg80211, the ssids pointer may be valid even when n_ssids is 0, leading to an out-of-bounds memory access when the pointer is dereferenced. This vulnerability affects Siemens industrial networking products that incorporate the vulnerable Linux kernel wireless subsystem, including the RUGGEDCOM RST2428P and SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family devices running SINEC OS. The vulnerability was disclosed on August 12, 2025, with subsequent advisory updates through February 25, 2026, to clarify affected product configurations and remove rejected CVEs from related advisories. Organizations should apply vendor-provided firmware updates and follow defense-in-depth practices for industrial control systems.

Vendor: Siemens
Product: RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS: Unknown
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 wireless networking infrastructure including RUGGEDCOM RST2428P and SCALANCE XC/XR series switches in manufacturing, energy, transportation, and critical infrastructure sectors. Security teams responsible for OT/ICS environments with wireless connectivity requirements. System integrators and managed service providers supporting Siemens industrial networking deployments.

Technical summary

The vulnerability exists in the iwlwifi mvm (mac80211 virtual monitor) driver's handling of SSID scan requests. The driver code fails to verify that n_ssids (the count of SSIDs to scan for) is greater than zero before accessing the ssids array pointer. In certain cfg80211 configurations, a valid pointer may exist even with n_ssids=0, causing the driver to read beyond allocated memory boundaries when attempting to access ssids[0] or subsequent elements. This represents a classic missing bounds check vulnerability (CWE-20: Improper Input Validation) in kernel-mode wireless driver code. The flaw could potentially lead to information disclosure, denial of service through kernel panic, or undefined behavior depending on memory layout. Affected Siemens products incorporate this vulnerable driver code in their SINEC OS firmware for industrial wireless networking applications.

Defensive priority

medium

Recommended defensive actions

Apply Siemens firmware updates for affected SCALANCE and RUGGEDCOM products when available per vendor advisory SSA-355557
Verify device configuration against Siemens ProductCERT guidance to determine actual exposure
Implement network segmentation for industrial wireless infrastructure per CISA ICS recommended practices
Monitor for anomalous wireless driver behavior or system crashes that could indicate exploitation attempts
Review and update incident response procedures for industrial control system wireless components

Evidence notes

The vulnerability description indicates this is a bounds-checking defect in the iwlwifi mvm (mac80211 virtual monitor) driver where n_ssids is not validated before accessing the ssids pointer. The CISA CSAF advisory ICSA-25-226-07 was initially published on 2025-08-12 and subsequently modified on 2026-02-12, 2026-02-24, and 2026-02-25 to correct affected product listings and clarify configurations. The February 25, 2026 update specifically republished based on Siemens ProductCERT SSA-355557 advisory. The threat assessment in the source marks this CVE as 'Misinformed' for the listed product IDs, suggesting potential advisory corrections or clarifications regarding actual impact.

Official resources

2025-08-12