CVE-2025-40938: A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected device stores sensitive…

CVE-2025-40938 · Severity: high · CVSS 8.1 · Published 2025-12-09

A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected device stores sensitive information in the firmware. This could allow an attacker to access and misuse this information, potentially impacting the device’s confidentiality, integrity, and availability.

Technologies: Siemens SIMATIC CN 4100, Siemens Simatic Cn 4100 Firmware. Vendors: Siemens.

Quick answers

Is CVE-2025-40938 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-40938 being exploited in the wild.
How severe is CVE-2025-40938?
High severity, with a CVSS score of 8.1, published 9 December 2025.
Which products and versions are affected?
Siemens SIMATIC CN 4100, Siemens Simatic Cn 4100 Firmware. The advisory does not name versions.
Is there a fix for CVE-2025-40938?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2025-40938?
Check whether you run Siemens SIMATIC CN 4100 or Siemens Simatic Cn 4100 Firmware. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • Siemens SIMATIC CN 4100
  • Siemens Simatic Cn 4100 Firmware

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