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CVE-2024-36031 Siemens CVE debrief

A critical vulnerability in the Linux kernel's key management subsystem allows unconditional overwriting of key expiration times during instantiation, causing DNS resolution failures by setting expiration to TIME64_MAX and disabling further DNS updates. The vulnerability affects Siemens industrial networking products running SINEC OS, including RUGGEDCOM RST2428P and SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family devices. The issue stems from the kernel unconditionally calling key_set_expiry during key instantiation, which defaults keys to permanent status regardless of user-space configured expiration times. This breaks DNS resolution workflows that rely on time-limited key caching with periodic updates. Siemens has released firmware updates to address this vulnerability.

Vendor
Siemens
Product
RUGGEDCOM RST2428P (6GK6242-6PA00)
CVSS
CRITICAL 9.8
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 including SCALANCE XC/XR/XCM/XRM/XCH/XRH series switches and RUGGEDCOM RST2428P devices in manufacturing, energy, transportation, and critical infrastructure sectors where reliable DNS resolution is essential for operational technology networks.

Technical summary

The vulnerability exists in the Linux kernel keys subsystem where key_set_expiry is unconditionally invoked during key instantiation, overwriting any expiration time previously configured by user-space. This causes the key expiration to default to TIME64_MAX (permanent), which specifically disrupts DNS resolution mechanisms that depend on time-bounded key caching with periodic refresh cycles. The fix restores conditional logic ensuring key_set_expiry is only called when the pre-parser explicitly sets a specific expiry value. The CVSS 3.1 score of 9.8 reflects network accessibility, low attack complexity, and no required privileges, with high impacts across all three security dimensions. Affected Siemens products utilize SINEC OS firmware based on the vulnerable Linux kernel versions.

Defensive priority

critical

Recommended defensive actions

  • Apply vendor firmware update to V3.1 or later version for affected Siemens SCALANCE and RUGGEDCOM devices
  • Review DNS resolution configurations on affected industrial control systems to verify proper key expiration behavior after patching
  • Monitor for anomalous DNS resolution patterns that may indicate exploitation attempts
  • Implement network segmentation for industrial control systems to limit exposure of key management interfaces
  • Follow CISA ICS recommended practices for defense-in-depth strategies for industrial control systems

Evidence notes

Vulnerability description and affected products confirmed through CISA ICS advisory ICSA-25-226-15, which references Siemens ProductCERT advisory SSA-613116. CVSS 3.1 vector AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H indicates network-exploitable, low-complexity attack with no privileges required, yielding high impact across confidentiality, integrity, and availability. Remediation guidance specifies update to V3.1 or later version. Advisory revision history shows multiple updates through 2026-02-25 correcting affected product lists and removing rejected CVEs.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-36031 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-36031

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

  • CVE-2024-36031 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-36031

    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-25-226-15.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-613116.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-613116.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-25-226-15

    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.