Critical severity · published Dec 9, 2025
CVE-2025-40938
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1)
9.8
CVSS
0.4%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SC
Simatic CN 4100 Firmware · Siemens
before 4.0.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-40938
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-40938
Vendor Advisory
https://cert-portal.siemens.com/productcert/html/ssa-416652.html
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