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CVE-2024-27397 Siemens CVE debrief

CVE-2024-27397 is a vulnerability in the Linux kernel's netfilter nf_tables subsystem affecting Siemens SIMATIC S7-1500 TM MFP GNU/Linux subsystem. The issue involves a race condition where set elements could expire during unfinished control plane transactions, potentially leading to use-after-free conditions. The vulnerability was resolved by adding a timestamp field at transaction start, stored in the nftables per-netns area, with set backend operations (.insert, .deactivate, sync gc path) using this timestamp rather than current time to prevent element expiration during active transactions. Packet path operations (.lookup, .update) and lockless operations (.get, dump) continue using current time, as does async garbage collection from workqueues. The CVSS 3.1 vector indicates local attack vector, high attack complexity, low privileges required, with high impacts to confidentiality, integrity, and availability. No patch is currently available per the vendor advisory; mitigations focus on restricting interactive shell access to trusted personnel and running only trusted applications.

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
2024-05-14
Original CVE updated
2026-08-04
Advisory published
2024-05-14
Advisory updated
2026-08-04

Who should care

Organizations operating Siemens SIMATIC S7-1500 TM MFP industrial control systems with enabled GNU/Linux subsystem, OT security teams managing embedded Linux environments in ICS/SCADA infrastructure, and asset owners requiring defense-in-depth strategies where kernel patches are not immediately deployable.

Technical summary

The vulnerability exists in the Linux kernel netfilter nf_tables subsystem's handling of set element timeouts. Without proper timestamp synchronization, set elements could expire while control plane transactions remain unfinished, creating a window for use-after-free exploitation. The fix introduces transaction-scoped timestamps stored in per-netns nftables state, ensuring .insert, .deactivate, and synchronous garbage collection paths evaluate expiration against transaction start time rather than current time. Asynchronous paths (packet processing, lockless lookups, async GC) appropriately retain current time checks. The affected Siemens product embeds a GNU/Linux subsystem where this kernel vulnerability is exposed.

Defensive priority

high

Recommended defensive actions

  • Restrict interactive shell access to the GNU/Linux subsystem to trusted personnel only
  • Execute only applications from trusted sources
  • Monitor for vendor security updates from Siemens CERT
  • Apply defense-in-depth strategies per CISA ICS recommended practices
  • Review network segmentation for industrial control systems running affected products

Evidence notes

Vulnerability description and resolution details sourced from CISA CSAF advisory ICSA-24-102-01. Vendor confirmed as Siemens with affected product SIMATIC S7-1500 TM MFP GNU/Linux subsystem. CVSS 3.1 score 7.0 (HIGH) with vector AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Remediation status indicates no fix available as of advisory publication.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-27397 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-27397

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

  • CVE-2024-27397 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-27397

    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.