CVE-2025-40939
Medium
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.
SeverityMedium
CVSS4.6
Exploit probability—
ProductSiemens Simatic Cn 4100 Firmware
PublishedDec 9, 2025
First seenDec 9, 2025
Weakness typeCWE-284Improper access control
How to fix
Update
- siemens simatic_cn_4100_firmware4.0.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| siemens simatic_cn_4100_firmware | v < 4.0.1 | 4.0.1 |
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