PatchSiren cyber security CVE debrief

CVE-2024-26804 Siemens CVE debrief

This CVE addresses a vulnerability in the Linux kernel's IP tunnel implementation where perpetual headroom growth could occur. The issue was resolved by preventing unbounded headroom expansion in net/ip_tunnel. The vulnerability affects Siemens industrial networking products running SINEC OS, specifically the RUGGEDCOM RST2428P and SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family devices. CISA published this advisory on August 12, 2025, with subsequent updates through February 25, 2026, including corrections to affected product lists and removal of rejected CVEs. The threat assessment categorizes the impact as 'Misinformed' per the source advisory. No CVSS score or severity rating is available in the provided source corpus.

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 SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family switches, RUGGEDCOM RST2428P devices, or other affected industrial networking equipment utilizing IP tunnel features. OT security teams and network administrators responsible for critical infrastructure networks should prioritize firmware updates.

Technical summary

The vulnerability exists in the Linux kernel's IP tunnel (net/ip_tunnel) implementation where perpetual headroom growth could occur, potentially leading to resource exhaustion or packet processing issues. The fix prevents unbounded headroom expansion. This affects Siemens industrial networking products that utilize IP tunneling functionality within their SINEC OS operating system.

Defensive priority

medium

Recommended defensive actions

Review Siemens ProductCERT advisory SSA-613116 for detailed product-specific patch information
Verify SINEC OS version on affected SCALANCE and RUGGEDCOM devices
Apply vendor-provided firmware updates to address the underlying Linux kernel vulnerability
Monitor network traffic for anomalous IP tunnel behavior as a detection control
Follow CISA ICS recommended practices for defense-in-depth strategies

Evidence notes

Source indicates this vulnerability was resolved in the Linux kernel. The CISA CSAF advisory ICSA-25-226-15 underwent multiple revisions: initial publication (2025-08-12), corrected affected products (2026-02-12), removed rejected CVEs and unsupported version notes (2026-02-24), and final republication based on Siemens ProductCERT SSA-613116 (2026-02-25). Threat category 'Misinformed' assigned to affected product IDs CSAFPID-0001, CSAFPID-0003, CSAFPID-0004.

Official resources

2025-08-12