PatchSiren

PatchSiren cyber security CVE debrief

CVE-2024-27053 Siemens CVE debrief

A critical vulnerability (CVSS 9.1) exists in the Linux kernel's wilc1000 Wi-Fi driver, specifically in the connection path where improper RCU (Read-Copy-Update) synchronization can lead to use-after-free conditions. The vulnerability was published on April 9, 2024, and affects Siemens SIMATIC S7-1500 TM MFP industrial control systems through their GNU/Linux subsystem. The flaw allows network-based attackers to achieve high confidentiality impact and high availability impact without requiring authentication or user interaction. As of the source advisory's last modification on May 14, 2026, no patch is available from the vendor.

Vendor
Siemens
Product
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS
CRITICAL 9.1
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

Organizations operating Siemens SIMATIC S7-1500 TM MFP industrial control systems with the GNU/Linux subsystem enabled, particularly those in manufacturing, process control, and critical infrastructure sectors. Security teams responsible for OT/ICS environments, network administrators managing industrial Wi-Fi deployments, and compliance officers tracking unpatched critical vulnerabilities should prioritize this issue.

Technical summary

The vulnerability resides in the wilc1000 Wi-Fi driver within the Linux kernel, specifically in the connection path where RCU (Read-Copy-Update) synchronization is improperly handled. RCU is a synchronization mechanism that allows read-heavy operations to proceed without locking, but requires careful handling of grace periods and callback execution. The improper usage in the connect path can result in use-after-free memory corruption, enabling remote attackers to potentially read sensitive information or cause denial of service conditions. The attack requires network access but no authentication, making it particularly dangerous for exposed industrial control systems.

Defensive priority

critical

Recommended defensive actions

  • Restrict interactive shell access to the GNU/Linux subsystem to trusted personnel only
  • Build and run applications exclusively from trusted sources
  • Monitor for future Siemens security advisories regarding patch availability
  • Apply network segmentation to limit exposure of affected industrial control systems
  • Review CISA ICS recommended practices for defense-in-depth strategies

Evidence notes

Vulnerability disclosed through CISA ICS advisory ICSA-24-102-01 and Siemens security advisory SSA-265688. The source advisory has undergone ten revision updates between April 2024 and September 2025, with this CVE remaining listed throughout. The CVSS vector confirms network attack vector with low attack complexity.

Official resources

public