---
title: "Siemens SINEMA Remote Connect Flaws Expose Critical Systems to Attacks"
short_title: "Siemens SINEMA server vulnerabilities patched"
description: "Two critical vulnerabilities in Siemens SINEMA Remote Connect Server (CVE-2025-40818, CVE-2025-40819) enable MITM attacks and license bypass. Update now to secure industrial systems."
author: "Vitus"
date: 2025-01-24
categories: [Cybersecurity, Vulnerabilities]
tags: [siemens, sinema, cve-2025-40818, cve-2025-40819, industrial-security]
score: 0.75
cve_ids: [CVE-2025-40818, CVE-2025-40819]
---
TL;DR
Siemens has patched two critical vulnerabilities in its SINEMA Remote Connect Server that could allow authenticated attackers to impersonate the server, decrypt traffic, or bypass licensing restrictions. The flaws, tracked as CVE-2025-40818 and CVE-2025-40819, affect all versions prior to V3.2 SP4. Organizations using this software are urged to update immediately to mitigate risks of man-in-the-middle (MITM) attacks and unauthorized access.
---
Main Content
Introduction
Industrial networks rely on secure remote access solutions to maintain operational efficiency and safety. However, vulnerabilities in these systems can expose critical infrastructure to cyber threats. Siemens recently addressed two significant security flaws in its SINEMA Remote Connect Server, a widely used platform for managing remote connections in industrial environments. These vulnerabilities could enable attackers to compromise sensitive communications or bypass licensing controls, posing severe risks to affected organizations.
---
Key Points
- Vulnerabilities Identified: Two flaws—CVE-2025-40818 (Incorrect Permission Assignment) and CVE-2025-40819 (Incorrect Authorization)—affect Siemens SINEMA Remote Connect Server versions prior to V3.2 SP4.
- Exploitation Risks: Successful exploitation could lead to man-in-the-middle (MITM) attacks, traffic decryption, or unauthorized access to services trusting compromised certificates.
- Affected Sectors: Primarily impacts critical manufacturing sectors worldwide, with deployments in industrial environments globally.
- Mitigation: Siemens has released V3.2 SP4 to address these issues. Users are advised to update immediately and follow recommended security practices.
---
Technical Details
#### Affected Products
- Siemens SINEMA Remote Connect Server: All versions prior to V3.2 SP4.
#### Vulnerability Breakdown
1. CVE-2025-40818 (Incorrect Permission Assignment for Critical Resource - CWE-732)
- CVSS v3.1 Score: 3.3 (Low)
- Vector: `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`
- Description: The server stores private SSL/TLS keys without proper protection, allowing authenticated users with server access to read these keys. Attackers could impersonate the server, enabling MITM attacks, traffic decryption, or unauthorized access to trusted services.
2. CVE-2025-40819 (Incorrect Authorization - CWE-863)
- CVSS v3.1 Score: 4.3 (Medium)
- Vector: `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N`
- Description: The server fails to validate license restrictions against its database properly. Attackers with database access can modify the system_ticketinfo table to bypass licensing limitations, enabling unauthorized use of the software.
---
Impact Assessment
The vulnerabilities in SINEMA Remote Connect Server pose significant risks to industrial environments:
- MITM Attacks: Attackers could intercept and manipulate communications between devices, leading to data breaches or sabotage.
- Traffic Decryption: Sensitive industrial data transmitted over compromised connections could be decrypted and exposed.
- License Bypass: Unauthorized users could exploit the system beyond its intended scope, violating compliance and licensing agreements.
- Operational Disruption: Successful exploitation could disrupt critical manufacturing processes, leading to financial losses or safety incidents.
---
Mitigation Steps
Siemens has released V3.2 SP4 to address these vulnerabilities. Users are advised to:
1. Update Immediately: Apply the latest patch (V3.2 SP4 or later) to mitigate risks. Download the update [here](https://support.industry.siemens.com/cs/ww/en/view/109995084/).
2. Restrict Network Access: Ensure control system devices are not accessible from the internet. Use firewalls to isolate industrial networks from business networks.
3. Use Secure Remote Access: When remote access is required, employ Virtual Private Networks (VPNs) and ensure they are updated to the latest version.
4. Follow Siemens Guidelines: Adhere to Siemens’ [operational guidelines for industrial security](https://www.siemens.com/cert/operational-guidelines-industrial-security) and product manuals.
5. Monitor for Suspicious Activity: Implement intrusion detection systems and monitor for signs of unauthorized access or exploitation.
For additional guidance, refer to CISA’s [recommended practices for industrial control systems (ICS)](https://www.cisa.gov/resources-tools/resources/ics-recommended-practices).
---
Conclusion
The discovery of CVE-2025-40818 and CVE-2025-40819 in Siemens SINEMA Remote Connect Server underscores the importance of robust security practices in industrial environments. Organizations must prioritize patching vulnerable systems and implementing defensive measures to prevent exploitation. As cyber threats evolve, proactive security strategies—such as regular updates, network segmentation, and secure remote access—are essential to safeguarding critical infrastructure.
For more details, refer to Siemens’ [security advisory SSA-626856](https://cert-portal.siemens.com/productcert/html/ssa-626856.html) and CISA’s [ICS advisory](https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-06).
---
References
[^1]: Siemens ProductCERT. "[SSA-626856: Vulnerabilities in SINEMA Remote Connect Server](https://cert-portal.siemens.com/productcert/html/ssa-626856.html)". Retrieved 2025-01-24.
[^2]: CISA. "[ICS Advisory (ICSA-25-345-06): Siemens SINEMA Remote Connect Server](https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-06)". Retrieved 2025-01-24.
[^3]: MITRE. "[CWE-732: Incorrect Permission Assignment for Critical Resource](https://cwe.mitre.org/data/definitions/732.html)". Retrieved 2025-01-24.
[^4]: MITRE. "[CWE-863: Incorrect Authorization](https://cwe.mitre.org/data/definitions/863.html)". Retrieved 2025-01-24.