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CVE-2024-50010 Siemens CVE debrief

A race condition in the Linux kernel's execve() path could trigger spurious kernel warnings (WARN_ON) when the noexec mount flag is toggled concurrently with program execution. The vulnerable code path contained a redundant path_noexec() check wrapped in WARN_ON that was originally intended for debugging but could fire falsely due to the non-atomic nature of the check versus the actual permission validation. This affects availability by potentially flooding logs with unwarranted warnings, though the underlying permission checks remain correct. The issue was resolved by removing the WARN_ON while retaining the redundant check for defensive programming. Siemens SIMATIC S7-1500 TM MFP devices running the GNU/Linux subsystem are affected; no patch is currently available from the vendor.

Vendor
Siemens
Product
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
CVSS
MEDIUM 4.7
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

Operators of Siemens SIMATIC S7-1500 TM MFP industrial control systems; security teams monitoring OT/ICS environments; Linux kernel maintainers and distributors; organizations with defense-in-depth requirements for critical infrastructure

Technical summary

The Linux kernel's execve() implementation contained a racy WARN_ON check for path_noexec() that could trigger spurious warnings when the noexec mount flag changed concurrently with program execution. The check was redundant—actual permission validation occurred earlier in the call chain—but the WARN_ON remained from prior refactoring commits 633fb6ac3980 and 0fd338b2d2cd. The race is benign from a security perspective (permissions are checked correctly) but causes availability impact through log flooding. The fix removes the WARN_ON while preserving the defensive redundant check. Siemens SIMATIC S7-1500 TM MFP devices with GNU/Linux subsystem are affected with no current patch available.

Defensive priority

medium

Recommended defensive actions

  • Restrict interactive shell access to the GNU/Linux subsystem on affected Siemens devices to trusted personnel only
  • Build and execute only applications from trusted sources on affected systems
  • Monitor kernel logs for excessive warning patterns that may indicate exploitation attempts
  • Apply vendor patches when released by Siemens
  • Review and implement CISA ICS recommended practices for defense-in-depth

Evidence notes

The vulnerability description confirms this is a kernel-level race condition in execve() handling, not a privilege escalation or code execution flaw. The WARN_ON removal indicates this was a diagnostic issue rather than a security boundary violation. CISA CSAF advisory ICSA-24-102-01 and Siemens SSA-265688 document affected products.

Official resources

2024-04-09