CVE-2024-42229 Siemens CVE debrief

Who should care

OT security engineers managing Siemens SCALANCE or RUGGEDCOM infrastructure; industrial network administrators responsible for firmware maintenance; cryptography engineers evaluating kernel-level key handling; compliance auditors assessing cryptographic implementation standards; incident response teams investigating potential key exposure in industrial environments

Technical summary

The vulnerability exists in the Linux kernel's crypto API, specifically the AEAD (Authenticated Encryption with Associated Data) and symmetric cipher implementations. After cryptographic operations complete, key buffers are not explicitly zeroized (cleared), leaving sensitive key material resident in memory. This violates cryptographic best practices for secure key handling and could allow an attacker with memory read capabilities to recover key material. The flaw affects Siemens industrial networking products incorporating vulnerable Linux kernel versions within SINEC OS, including SCALANCE switch families and RUGGEDCOM devices. Exploitation requires either local access to execute memory disclosure primitives or adjacent network positioning to leverage other vulnerabilities for memory access. The CVSS 4.1 MEDIUM score reflects this attack complexity constraint rather than low severity of the cryptographic weakness itself.

Defensive priority

medium

Recommended defensive actions

• Review Siemens SSA-355557 security advisory for definitive affected product and patch status
• Verify SINEC OS and firmware versions on SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 and RUGGEDCOM RST2428P deployments
• Apply Siemens-provided firmware updates when available per vendor maintenance schedule
• Implement network segmentation for industrial control systems per CISA ICS recommended practices
• Monitor for anomalous memory access patterns or privilege escalation attempts on affected devices
• Ensure cryptographic key rotation procedures account for potential historical exposure windows

Evidence notes

CISA CSAF advisory ICSA-25-226-07 published 2025-08-12; revised 2026-02-12, 2026-02-24, and 2026-02-25 to correct product scope and remove rejected CVEs. Siemens SSA-355557 provides authoritative product-specific guidance. CVSS 4.1 MEDIUM severity reflects limited attack surface requiring local or adjacent network access to exploit memory disclosure.

Official resources