CVE-2025-40941: A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1)

Q: How do I fix CVE-2025-40941?

simatic cn 4100 firmware: upgrade to 4.0.1. Exact commands for each OS are on this page.

Q: Is CVE-2025-40941 being exploited?

CVE-2025-40941 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2025-40941 affect?

CVE-2025-40941 affects simatic cn 4100 firmware. Severity is medium (CVSS 4.3). A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected devices exposes server information in its responses. This could allow an attacker with network access to gain useful information, increasing the l

Q: How urgent is CVE-2025-40941?

Priority 20/100. No elevated risk signals yet.

Routine

MEDIUM 4.3UPGRADE

CVE-2025-40941 is a medium-severity flaw (CVSS 4.3) affecting simatic cn 4100 firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected devices exposes server information in its responses. This could allow an attacker with network access to gain useful information, increasing the likelihood of targeted attacks.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	4.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.3% (top 80%)
CISA exploited list	No
Weakness	CWE-200
Published	2025-12-09
Last modified	2026-10-23

Publisher (CNA): Siemens AG · Vendor: siemens

Last updated 2026-10-23 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-12-09 16:17 UTCPublished CVE record published
2026-10-23 22:10 UTCUpdated Record last modified

siemens simatic cn 4100 firmware UPGRADE

Affected: < 4.0.1

Fixed in: 4.0.1

Safe to downgrade to: no unaffected older release

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-40941?

simatic cn 4100 firmware: upgrade to 4.0.1. Exact commands for each OS are on this page.

Is CVE-2025-40941 being exploited?

CVE-2025-40941 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2025-40941 affect?

CVE-2025-40941 affects simatic cn 4100 firmware. Severity is medium (CVSS 4.3). A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1). The affected devices exposes server information in its responses. This could allow an attacker with network access to gain useful information, increasing the l

How urgent is CVE-2025-40941?

Priority 20/100. No elevated risk signals yet.

Related CVEs

CVE-2026-22925 HIGH 7.5 UPGRADE A vulnerability has been identified in SIMATIC CN 4100 (All versions < V5.0)
CVE-2023-29131 HIGH 7.4 UPGRADE A vulnerability has been identified in SIMATIC CN 4100 (All versions < V2.5)
CVE-2025-40937 HIGH 8.3 UPGRADE A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1)
CVE-2025-40938 HIGH 8.1 UPGRADE A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1)
CVE-2025-40940 MEDIUM 4.9 UPGRADE A vulnerability has been identified in SIMATIC CN 4100 (All versions < V4.0.1)

References

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