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CVE-2024-57979 Siemens CVE debrief

A use-after-free vulnerability in the Pulse Per Second (PPS) subsystem of the Linux kernel affects the GNU/Linux subsystem embedded in Siemens SIMATIC S7-1500 TM MFP industrial controllers. The flaw, published 2024-04-09, allows a local attacker with low privileges to achieve high confidentiality, integrity, and availability impact without user interaction. The vulnerability stems from improper memory management in the PPS driver code where a freed object may still be referenced, leading to potential code execution or system crash. Siemens has not released a patch as of the 2026-05-14 advisory update; mitigation relies on restricting interactive shell access to trusted personnel and ensuring only trusted applications are built and executed on the affected subsystem. The CISA advisory (ICSA-24-102-01) has undergone ten revision cycles, with the most significant updates adding numerous CVEs in 2025, indicating ongoing security review of the product's Linux-based components.

Vendor
Siemens
Product
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-14
Original CVE updated
2026-07-28
Advisory published
2026-07-14
Advisory updated
2026-07-28

Who should care

Industrial control system operators deploying Siemens SIMATIC S7-1500 TM MFP controllers in manufacturing, process control, or critical infrastructure environments. Security teams responsible for embedded Linux hardening in OT environments. Asset owners with hybrid PLC/Linux architectures requiring defense-in-depth strategies. Compliance officers tracking CVE coverage for NERC CIP, IEC 62443, or similar frameworks.

Technical summary

The vulnerability exists in the Pulse Per Second (PPS) kernel driver, a timing subsystem used for high-precision time synchronization. A use-after-free condition occurs when a PPS-related object is freed but subsequently accessed, potentially allowing arbitrary code execution in kernel context. The attack requires local access with low privileges, making it exploitable by any user with shell access to the GNU/Linux subsystem. The SIMATIC S7-1500 TM MFP embeds a full GNU/Linux environment alongside its PLC runtime, expanding the attack surface compared to traditional PLCs. The CVSS 3.1 score of 7.8 reflects the high impact potential despite local attack vector constraints. No firmware update or kernel patch is currently available from Siemens, making operational mitigations the primary defense.

Defensive priority

HIGH

Recommended defensive actions

  • Restrict interactive shell access to the GNU/Linux subsystem to authorized personnel only
  • Implement application whitelisting to ensure only trusted, verified applications execute on the embedded Linux environment
  • Monitor for anomalous process behavior or unexpected PPS-related kernel messages in system logs
  • Apply defense-in-depth controls per CISA ICS recommended practices for industrial control systems
  • Subscribe to Siemens ProductCERT security advisories for patch availability notifications
  • Review and update incident response procedures for embedded controller compromises
  • Segment affected controllers from untrusted networks to limit lateral movement opportunities

Evidence notes

CVE description confirms 'pps: Fix a use-after-free' as the vulnerability type. CVSS 3.1 vector AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H indicates local attack vector with low attack complexity and low privileges required, yielding high impact across all three security dimensions. Siemens advisory SSA-265688 cross-referenced in CISA CSAF source. Remediation status explicitly marked 'none_available' with mitigation guidance provided.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-57979 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-57979

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

  • CVE-2024-57979 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-57979

    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/2024/icsa-24-102-01.json

    cisa_csaf

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/csaf/ssa-265688.json

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://cert-portal.siemens.com/productcert/html/ssa-265688.html

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://www.cisa.gov/news-events/ics-advisories/icsa-24-102-01

    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.