CVE-2025-40939 | Vulnetix

CVE-2025-40939 PUBLISHED CVSS 4.6 MEDIUM

Reported by siemens · Published December 9, 2025

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.

Fixed versions

Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.

Package	Ecosystem	Fixed in
SIMATIC CN 4100	Siemens	4.0.1
simatic_cn_4100_firmware	siemens	4.0.1

Risk scores

CVSS 3.1

4.6

CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Vendor	Product	Versions
Siemens	SIMATIC CN 4100	0
Siemens	SIMATIC CN 4100	0

Timeline

Dec 9, 2025 CVE Published
Dec 9, 2025 EPSS Score (30 in total, the first dated here)
Mar 17, 2026 Security Advisory (3 in total, the first dated here)
Jun 8, 2026 Coalition ESS Score

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vulnetix vdb fixes CVE-2025-40939

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References

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