---
title: "Siemens IAM Client Vulnerability Exposes Systems to MITM Attacks (CVE-2025-40800)"
short_title: "Siemens IAM Client flaw enables MITM attacks"
description: "Siemens warns of a high-severity vulnerability (CVE-2025-40800) in its IAM Client, enabling man-in-the-middle attacks. Learn mitigation steps and affected products."
author: "Vitus"
date: 2025-01-24
categories: [Cybersecurity, Vulnerabilities]
tags: [siemens, cve-2025-40800, mitm, industrial-security, tls]
score: 0.78
cve_ids: [CVE-2025-40800]
---
TL;DR
Siemens has disclosed a high-severity vulnerability (CVE-2025-40800) in its Identity and Access Management (IAM) Client, affecting multiple products. The flaw, caused by improper certificate validation, allows unauthenticated remote attackers to perform man-in-the-middle (MITM) attacks. Siemens has released patches for most affected products, but no fix is currently available for COMOS V10.6. Organizations are urged to apply updates and follow recommended security practices to mitigate risks.
---
Main Content
Critical Siemens IAM Client Vulnerability Exposes Industrial Systems to MITM Attacks
Siemens has issued a security advisory warning users about a high-severity vulnerability in its Identity and Access Management (IAM) Client, which could enable attackers to intercept sensitive communications. The flaw, tracked as CVE-2025-40800, stems from improper certificate validation during TLS connections to authorization servers. If exploited, this vulnerability could allow unauthenticated remote attackers to perform man-in-the-middle (MITM) attacks, compromising the confidentiality and integrity of data.
This advisory is particularly critical for organizations in critical manufacturing sectors, where Siemens products are widely deployed. Below, we break down the key details, technical implications, and mitigation steps to help organizations secure their systems.
---
Key Points
- Vulnerability ID: CVE-2025-40800 (CVSS v4 score: 9.1 | CVSS v3.1 score: 7.4)
- Affected Products: Multiple Siemens products, including COMOS V10.6, NX, Simcenter 3D, Simcenter Femap, and Solid Edge
- Exploitation Risk: Remote attackers can perform MITM attacks without authentication
- Mitigation: Siemens has released patches for most affected products, but no fix is available for COMOS V10.6
- Impact: Compromise of sensitive data, unauthorized access, and potential disruption of industrial operations
---
Technical Details
#### Affected Products
Siemens has confirmed that the following products and versions are vulnerable to CVE-2025-40800:
- COMOS V10.6: All versions (no fix currently available)
- NX V2412: All versions prior to 2412.8700
- NX V2506: All versions prior to 2506.6000
- Simcenter 3D: All versions prior to 2506.6000
- Simcenter Femap: All versions prior to 2506.0002
- Solid Edge SE2025: All versions prior to V225.0 Update 10
- Solid Edge SE2026: All versions prior to V226.0 Update 1
#### Vulnerability Overview
The vulnerability is classified as CWE-295: Improper Certificate Validation[^1]. The IAM Client in affected Siemens products fails to validate server certificates during TLS handshakes with authorization servers. This oversight creates an opportunity for attackers to intercept and manipulate communications between the client and server, enabling:
- Data interception: Capturing sensitive information transmitted over the network
- Session hijacking: Taking control of active sessions to impersonate legitimate users
- Data tampering: Altering data in transit to manipulate industrial processes or steal intellectual property
The CVSS v4 base score of 9.1 reflects the severity of this flaw, indicating a high risk of exploitation with significant potential impact on confidentiality and integrity.
#### Attack Vector
To exploit this vulnerability, an attacker must:
1. Be positioned between the IAM Client and the authorization server (e.g., on the same network or via a compromised router).
2. Intercept TLS traffic by presenting a malicious certificate that the client accepts due to improper validation.
3. Decrypt, modify, or inject data into the communication stream, enabling MITM attacks.
While the attack requires high complexity (e.g., network access and specialized tools), the potential impact on industrial systems makes it a critical concern for organizations.
---
Impact Assessment
#### Industrial and Operational Risks
Siemens products are widely used in critical manufacturing sectors, including automotive, aerospace, and energy. A successful MITM attack could lead to:
- Unauthorized access to sensitive design files, intellectual property, or operational data
- Disruption of industrial processes, leading to downtime or safety incidents
- Compliance violations, particularly in regulated industries where data integrity is mandatory
#### Global Deployment
The affected products are deployed worldwide, with Siemens headquartered in Germany. Organizations across North America, Europe, and Asia are potentially at risk, making this a global cybersecurity concern.
#### Exploitation Status
As of this writing, no public exploitation of CVE-2025-40800 has been reported. However, the high CVSS score and remote exploitability make it an attractive target for threat actors. Organizations are advised to prioritize patching and implement defensive measures to reduce exposure.
---
Mitigation Steps
Siemens has released patches for most affected products. Organizations should:
#### Apply Updates Immediately
- Solid Edge SE2025: Update to V225.0 Update 10 or later[^2]
- Solid Edge SE2026: Update to V226.0 Update 1 or later[^2]
- NX V2412: Update to V2412.8700 or later[^3]
- Simcenter Femap: Update to V2506.0002 or later[^4]
- NX V2506: Update to V2506.6000 or later[^3]
- Simcenter 3D: Update to V2506.6000 or later[^5]
- COMOS V10.6: No fix available—implement compensating controls (see below)
#### Compensating Controls for Unpatched Systems
For products without available patches (e.g., COMOS V10.6), Siemens recommends:
1. Network Segmentation: Isolate affected systems from business networks and the internet.
2. Firewall Rules: Restrict access to authorization servers and limit exposure to trusted IP addresses.
3. Monitoring: Deploy intrusion detection systems (IDS) to detect anomalous TLS traffic or certificate mismatches.
4. VPNs: Use Virtual Private Networks (VPNs) for remote access, ensuring they are updated to the latest version.
5. Industrial Security Guidelines: Follow Siemens’ [Operational Guidelines for Industrial Security](https://www.siemens.com/cert/operational-guidelines-industrial-security) to harden environments.
#### General Security Best Practices
CISA recommends the following measures to minimize risk:
- Minimize network exposure for control system devices, ensuring they are not accessible from the internet[^6].
- Locate control system networks behind firewalls and isolate them from business networks.
- Use secure remote access methods, such as VPNs, and ensure they are patched and configured securely.
- Conduct risk assessments before deploying defensive measures to avoid unintended disruptions.
For additional guidance, refer to CISA’s [Control Systems Security Recommended Practices](https://www.cisa.gov/resources-tools/resources/ics-recommended-practices)[^7].
---
Conclusion
The CVE-2025-40800 vulnerability in Siemens’ IAM Client poses a significant risk to organizations relying on affected products. While patches are available for most systems, the lack of a fix for COMOS V10.6 underscores the importance of proactive security measures, such as network segmentation and monitoring.
Organizations must act swiftly to apply updates, implement compensating controls, and follow industrial security best practices to mitigate the risk of MITM attacks. As cyber threats to industrial systems continue to evolve, staying vigilant and prioritizing cybersecurity is essential to safeguarding critical infrastructure.
For more information, refer to Siemens’ [ProductCERT Security Advisory (SSA-868571)](https://cert-portal.siemens.com/productcert/html/ssa-868571.html) and CISA’s [ICS Advisory (ICSA-25-345-04)](https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-04).
---
References
[^1]: MITRE. "[CWE-295: Improper Certificate Validation](https://cwe.mitre.org/data/definitions/295.html)". Retrieved 2025-01-24.
[^2]: Siemens. "[Solid Edge Support](https://support.sw.siemens.com/product/246738425/)". Retrieved 2025-01-24.
[^3]: Siemens. "[NX Support](https://support.sw.siemens.com/product/209349590/)". Retrieved 2025-01-24.
[^4]: Siemens. "[Simcenter Femap Support](https://support.sw.siemens.com/product/275652363/)". Retrieved 2025-01-24.
[^5]: Siemens. "[Simcenter 3D Support](https://support.sw.siemens.com/product/289054037/)". Retrieved 2025-01-24.
[^6]: CISA. "[ICS Alert: Control System Security](https://www.cisa.gov/uscert/ics/alerts/ICS-ALERT-10-301-01)". Retrieved 2025-01-24.
[^7]: CISA. "[Control Systems Security Recommended Practices](https://www.cisa.gov/resources-tools/resources/ics-recommended-practices)". Retrieved 2025-01-24.