PatchSiren cyber security CVE debrief

CVE-2024-27025 Siemens CVE debrief

A HIGH severity vulnerability (CVSS 8.8) in the Linux kernel's Network Block Device (nbd) subsystem affects Siemens SIMATIC S7-1500 TM MFP industrial controllers with GNU/Linux subsystem. The flaw involves a missing NULL check for nla_nest_start(), which may fail and return NULL, potentially leading to undefined behavior. Published 2024-04-09 and last modified 2026-05-14 per official CVE records. No patch is currently available from the vendor.

Vendor: Siemens
Product: SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS: HIGH 8.8
CISA KEV: Not listed in stored evidence
Original CVE published: 2024-04-09
Original CVE updated: 2026-05-14
Advisory published: 2024-04-09
Advisory updated: 2026-05-14

Who should care

Industrial control system operators, OT security teams, and organizations deploying Siemens SIMATIC S7-1500 TM MFP controllers with GNU/Linux subsystem enabled. Critical infrastructure sectors including manufacturing, energy, and water/wastewater that rely on these controllers for process automation.

Technical summary

The vulnerability exists in the Linux kernel's Network Block Device (nbd) implementation where nla_nest_start() may fail and return NULL without proper validation. The missing NULL check could lead to undefined behavior when processing netlink attributes. This affects the GNU/Linux subsystem on Siemens SIMATIC S7-1500 TM MFP programmable logic controllers. The CVSS 3.1 score of 8.8 reflects network attack vector, low attack complexity, no privileges required, user interaction required, and high impacts to confidentiality, integrity, and availability.

Defensive priority

HIGH

Recommended defensive actions

Restrict interactive shell access to the GNU/Linux subsystem to trusted personnel only
Build and run only applications from trusted sources
Monitor for vendor security updates from Siemens CERT
Apply defense-in-depth controls per CISA ICS recommended practices
Segment industrial control networks from untrusted networks

Evidence notes

CVE published 2024-04-09; modified 2026-05-14. Source advisory ICSA-24-102-01 from CISA CSAF. Vendor confirmed as Siemens with product SIMATIC S7-1500 TM MFP - GNU/Linux subsystem. CVSS 3.1 vector: AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. No fix available per vendor remediation statement.

Official resources

2024-04-09