CVE-2025-40759: High severity Siemens Simatic S7-plcsim vulnerability

Published Aug 12, 2025
·
Updated

A vulnerability has been identified in SIMATIC S7-PLCSIM V17 (All versions), SIMATIC STEP 7 V17 (All versions < V17 Update 9), SIMATIC STEP 7 V18 (All versions < V18 Update 6), SIMATIC STEP 7 V19 (All versions < V19 Update 4), SIMATIC STEP 7 V20 (All versions < V20 Update 4), SIMATIC WinCC V17 (All versions < V17 Update 9), SIMATIC WinCC V18 (All versions < V18 Update 6), SIMATIC WinCC V19 (All versions < V19 Update 4), SIMATIC WinCC V20 (All versions < V20 Update 4), SIMOCODE ES V17 (All versions), SIMOCODE ES V18 (All versions), SIMOCODE ES V19 (All versions), SIMOCODE ES V20 (All versions), SIMOTION SCOUT TIA V5.4 (All versions), SIMOTION SCOUT TIA V5.5 (All versions), SIMOTION SCOUT TIA V5.6 (All versions < V5.6 SP1 HF7), SIMOTION SCOUT TIA V5.7 (All versions), SINAMICS Startdrive V17 (All versions), SINAMICS Startdrive V18 (All versions), SINAMICS Startdrive V19 (All versions), SINAMICS Startdrive V20 (All versions), SIRIUS Safety ES V17 (TIA Portal) (All versions), SIRIUS Safety ES V18 (TIA Portal) (All versions), SIRIUS Safety ES V19 (TIA Portal) (All versions), SIRIUS Safety ES V20 (TIA Portal) (All versions), SIRIUS Soft Starter ES V17 (TIA Portal) (All versions), SIRIUS Soft Starter ES V18 (TIA Portal) (All versions), SIRIUS Soft Starter ES V19 (TIA Portal) (All versions), SIRIUS Soft Starter ES V20 (TIA Portal) (All versions), TIA Portal Cloud V17 (All versions), TIA Portal Cloud V18 (All versions), TIA Portal Cloud V19 (All versions < V5.2.1.1), TIA Portal Cloud V20 (All versions < V5.2.2.2). Affected products do not properly sanitize stored security properties when parsing project files. This could allow an attacker to cause a type confusion and execute arbitrary code within the affected application.

Affected Software

9 affected components
Siemens Simatic S7-plcsim=V17
Siemens SIMATIC STEP 7<V17 Update 9, <V18 Update 6, <V19 Update 4, <V20 Update 4
Siemens SIMATIC WinCC<V17 Update 9, <V18 Update 6, <V19 Update 4, <V20 Update 4
Siemens Simocode Es=V17, =V18, =V19, =V20
Siemens SIMOTION SCOUT TIA=V5.4, =V5.5, <V5.6 SP1 HF7, =V5.7
Siemens SINAMICS Startdrive=V17, =V18, =V19, =V20
Siemens SIRIUS Safety ES (TIA Portal)=V17, =V18, =V19, =V20
Siemens SIRIUS Soft Starter ES (TIA Portal)=V17, =V18, =V19, =V20
Siemens TIA Portal Cloud=V17, =V18, <V5.2.1.1, <V5.2.2.2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade SIMATIC STEP 7 V17 / SIMATIC WinCC V17 to a version that resolves this vulnerability.

    Fixed in V17 Update 9
  2. Upgrade

    Upgrade SIMATIC STEP 7 V18 / SIMATIC WinCC V18 to a version that resolves this vulnerability.

    Fixed in V18 Update 6
  3. Upgrade

    Upgrade SIMATIC STEP 7 V19 / SIMATIC WinCC V19 to a version that resolves this vulnerability.

    Fixed in V19 Update 4
  4. Upgrade

    Upgrade SIMATIC STEP 7 V20 / SIMATIC WinCC V20 to a version that resolves this vulnerability.

    Fixed in V20 Update 4
  5. Upgrade

    Upgrade SIMOTION SCOUT TIA V5.6 to a version that resolves this vulnerability.

    Fixed in V5.6 SP1 HF7
  6. Upgrade

    Upgrade TIA Portal Cloud V19 to a version that resolves this vulnerability.

    Fixed in V5.2.1.1
  7. Upgrade

    Upgrade TIA Portal Cloud V20 to a version that resolves this vulnerability.

    Fixed in V5.2.2.2

Event History

Aug 12, 2025
CVE Published
via MITRE·11:17 AM
Data Sourced
via MITRE·11:17 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·12:15 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2025-40759?

CVE-2025-40759 has been categorized as a high-severity vulnerability due to its potential impact on the affected Siemens software.

2

How do I fix CVE-2025-40759?

To remediate CVE-2025-40759, update all affected Siemens products to the latest available versions.

3

What software is affected by CVE-2025-40759?

CVE-2025-40759 affects multiple Siemens products including S7-PLCSIM, STEP 7 (versions up to V19 Update 4), and WinCC (all versions).

4

Can CVE-2025-40759 be exploited remotely?

Yes, CVE-2025-40759 can potentially be exploited remotely if the affected software is exposed to untrusted networks.

5

What are the potential consequences of CVE-2025-40759?

Exploitation of CVE-2025-40759 could lead to unauthorized access, manipulation of data, or disruption of system operations.

Contact

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