Siemens Mendix Runtime Vulnerability Exposes Sensitive User Data
A vulnerability in Siemens Mendix Runtime allows developers to unknowingly apply overly permissive access rules to System.User, exposing sensitive user data or privilege escalation within deployed Mendix applications.
Intelligence analysis by Llama
A documentation gap in Mendix's access rules leaves developers without sufficient guidance to configure access rules securely, potentially leading to unintended exposure of sensitive user data or privilege escalation.
Imagine you're building a digital app, but the instructions for keeping it safe are incomplete. This is what's happening with Siemens Mendix Runtime. A mistake in the instructions can let bad people get into the app and see things they shouldn't. It's like leaving a door unlocked.
Analysis
A Critical Documentation Gap
The Mendix documentation for access rules does not adequately describe the special behavior of the System.User entity, leaving developers without sufficient guidance to configure access rules securely. This documentation gap may lead application developers to unknowingly apply overly permissive access rules to System.User, resulting in unintended exposure of sensitive user data or privilege escalation within deployed Mendix applications.
Insecure Inherited Permissions
A common misconfiguration identified is with the anonymous user role with a System.User entity to gain access to all stored records, even though no access rights are explicitly configured on that role. Siemens recommends Mendix developers to review their access rules based on updated documentation.
Affected Products and Versions
The following versions of Siemens Mendix Runtime are affected: Mendix Runtime vers:all/* (CVE-2026-7891).
Key points
- A documentation gap in Mendix's access rules leaves developers without sufficient guidance to configure access rules securely.
- The vulnerability affects critical infrastructure sectors, including manufacturing.
- Siemens recommends Mendix developers to review their access rules based on updated documentation.
Siemens has released updated documentation to help developers configure access rules securely. By following these guidelines, developers can minimize the risk of exposing sensitive user data or enabling privilege escalation within deployed Mendix applications.
If left unaddressed, this vulnerability could lead to unintended exposure of sensitive user data or privilege escalation within deployed Mendix applications, potentially compromising the security of critical infrastructure sectors.
