Improper access control in SIMATIC CN 4100 - CVE-2025-40939
Published: December 10, 2025
Vulnerability identifier: #VU119800
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2025-40939
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Siemens
Affected software:
SIMATIC CN 4100
SIMATIC CN 4100
Detailed vulnerability description
The vulnerability allows a local attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to the affected device contains a USB port which allows unauthenticated connections. An attacker with physical access can bypass implemented security restrictions and perform a denial of service (DoS) attack.
How to mitigate CVE-2025-40939
Install updates from vendor's website.