CVE-2025-40566: A vulnerability has been identified in SIMATIC PCS neo V4.1 (All versions < V4.1 Update 3), SIMATIC PCS neo V5

Q: How do I fix CVE-2025-40566?

simatic pcs neo: upgrade to 4.1, 5.0. Exact commands for each OS are on this page.

Q: Is CVE-2025-40566 being exploited?

CVE-2025-40566 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-2025-40566 affect?

CVE-2025-40566 affects simatic pcs neo. Severity is high (CVSS 8.8). A vulnerability has been identified in SIMATIC PCS neo V4.1 (All versions < V4.1 Update 3), SIMATIC PCS neo V5.0 (All versions < V5.0 Update 1). Affected products do not correctly invalidate user sessions upon user logout. This could allow

This month

HIGH 8.8UPGRADE

CVE-2025-40566 is a high-severity flaw (CVSS 8.8) affecting simatic pcs neo. 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 PCS neo V4.1 (All versions < V4.1 Update 3), SIMATIC PCS neo V5.0 (All versions < V5.0 Update 1). Affected products do not correctly invalidate user sessions upon user logout. This could allow a remote unauthenticated attacker, who has obtained the session token by other means, to re-use a legitimate user's session even after logout.

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.5% (top 60%)
CISA exploited list	No
Weakness	CWE-613
Published	2025-05-13
Last modified	2026-06-17

Publisher (CNA): Siemens AG · Vendor: siemens

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-05-13 10:15 UTCPublished CVE record published
2026-06-17 09:21 UTCUpdated Record last modified

siemens simatic pcs neo UPGRADE

Affected: < 4.1 · < 5.0 · 4.1 update_1 · 4.1 update_2 · 5.0

Fixed in: 4.1, 5.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy simatic-pcs-neo || rpm -q simatic-pcs-neo || simatic-pcs-neo --version

2. UPGRADE to 4.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade simatic-pcs-neo

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade simatic-pcs-neo

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

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-2025-40566?

simatic pcs neo: upgrade to 4.1, 5.0. Exact commands for each OS are on this page.

Is CVE-2025-40566 being exploited?

CVE-2025-40566 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-2025-40566 affect?

CVE-2025-40566 affects simatic pcs neo. Severity is high (CVSS 8.8). A vulnerability has been identified in SIMATIC PCS neo V4.1 (All versions < V4.1 Update 3), SIMATIC PCS neo V5.0 (All versions < V5.0 Update 1). Affected products do not correctly invalidate user sessions upon user logout. This could allow

How urgent is CVE-2025-40566?

Priority 41/100. High severity

Software pages

Siemens vulnerabilities

Related CVEs

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References

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