Medium severity · published Dec 9, 2025
CVE-2025-40940
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1)
4.9
CVSS
0.4%
EPSS
No
On KEV
Description
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected application exhibits inconsistent SNMP behavior, such as unexpected service availability and unreliable configuration handling across protocol versions. This could allow an attacker to access sensitive data, potentially leading to a breach of confidentiality.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% 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-2025-40940
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-40940
Vendor Advisory
https://cert-portal.siemens.com/productcert/html/ssa-416652.html
More from Simatic CN 4100 Firmware
9.8
CVE-2025-39682
tls: fix handling of zero-length records on the rx_list
7.8
CVE-2026-31431
crypto: algif_aead - Revert to operating out-of-place
10.0
CVE-2024-32741
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V3.0)
10.0
CVE-2023-29131
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V2.5)
10.0
CVE-2023-29130
A vulnerability has been identified in SIMATIC CN 4100 (All versions < V2.5)