CVE-2025-40939
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-12-09

Last updated on: 2025-12-16

Assigner: Siemens AG

Description
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected device contains a USB port which allows unauthenticated connections. This could allow an attacker with physical access to the device to trigger reboot that could cause denial of service condition.
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Meta Information
Published
2025-12-09
Last Modified
2025-12-16
Generated
2026-06-16
AI Q&A
2025-12-09
EPSS Evaluated
2026-06-14
NVD
CVE-2025-40939
EUVD
EUVD-2025-201917
Affected Vendors & Products
Showing 2 associated CPEs
Vendor Product Version / Range
siemens simatic_cn_4100_firmware to 4.0.1 (inc)
siemens simatic_cn_4100 *
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-284 The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
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Executive Summary

This vulnerability exists in the SIMATIC CN 4100 device (all versions before V4.0.1) which has a USB port allowing unauthenticated connections. An attacker with physical access to the device can use this USB port to trigger a reboot, potentially causing a denial of service condition.

Impact Analysis

The vulnerability can impact you by allowing an attacker with physical access to the device to cause it to reboot unexpectedly. This can lead to a denial of service condition, disrupting the availability of the device and any services relying on it.

Mitigation Strategies

To mitigate this vulnerability, restrict physical access to the SIMATIC CN 4100 device to prevent unauthorized use of the USB port. Ensure that only trusted personnel can access the device physically, as the vulnerability requires physical access to trigger a reboot causing denial of service.

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