CVE-2025-40805
Authentication Bypass in Siemens API Enables Remote User Impersonation
Publication date: 2026-01-13
Last updated on: 2026-01-13
Assigner: Siemens AG
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| siemens | industrial_edge_device_kit | From 1.5 (inc) to 1.23 (inc) |
| siemens | simatic_hmi_unified_comfort_panels | to 21 (exc) |
| siemens | simatic_automation_workstations | * |
| siemens | simatic_hmi_unified_comfort_panels | 21 |
| siemens | simatic_hmi_unified_comfort_panels | 21.0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-639 | The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability is a critical authorization bypass in Siemens Industrial Edge Devices and SIMATIC HMI Unified Comfort Panels. It occurs because affected devices do not properly enforce user authentication on specific API endpoints. This flaw allows an unauthenticated remote attacker, who knows the identity of a legitimate user, to bypass authentication and impersonate that user, gaining unauthorized access to the system. [1, 2]
How can this vulnerability impact me? :
The vulnerability can have severe impacts including unauthorized remote access to affected devices, allowing attackers to impersonate legitimate users. This can lead to full compromise of confidentiality, integrity, and availability of the system, potentially disrupting industrial operations and exposing sensitive data. The vulnerability has a maximum severity score of 10.0, indicating critical risk. [1, 2]
What immediate steps should I take to mitigate this vulnerability?
To mitigate CVE-2025-40805, immediately restrict network access to affected Siemens devices to trusted parties only. Apply available updates: update Industrial Edge Device Kit to version V1.24.2 or later (arm64 and x86-64) and SIMATIC HMI Unified Comfort Panels to version V21 or later. For devices without available fixes, apply interim countermeasures as detailed in Siemens advisories and follow Siemens' operational guidelines for Industrial Security. Refer to Siemens' official support link for detailed mitigation instructions. [1, 2]
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided resources do not explicitly discuss the impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA. However, given that the vulnerability allows unauthenticated remote attackers to bypass authentication and impersonate legitimate users, it could potentially lead to unauthorized access to sensitive data, which may result in non-compliance with data protection regulations that require strict access controls and user authentication. Siemens recommends restricting network access to trusted parties and following security best practices to mitigate risks, which aligns with compliance requirements. Nonetheless, no direct statements about compliance impact are provided. [1, 2]