Critical Network Exposure in Development Tool
A high-severity vulnerability tracked as CVE-2026-112136 has been disclosed in Mendix Studio Pro, a low-code integrated development environment for professional developers. The flaw affects the product’s MCP Server component, which fails to properly restrict its HTTP listener to the loopback interface, potentially exposing it to remote systems.
According to Siemens ProductCERT, the vulnerability could allow an attacker with network access to interact with the MCP Server remotely. The issue has been assigned a CVSS v3.1 base score of 8.8 and a CVSS v4.0 base score of 9.2.
Affected Versions and Patches
The vulnerability impacts specific versions of Mendix Studio Pro 11:
- **Mendix Studio Pro 11**: All versions from V11.15.0 up to but not including V11.16.0
- **Mendix Studio Pro 11.12**: All versions from V11.12.6 up to but not including V11.12.7
Siemens has released patches to address the vulnerability. Users are advised to update to V11.16.0 or later for the Studio Pro 11 branch, or V11.12.7 or later for the 11.12 branch.
Technical Details
The vulnerability is classified under CWE-1327: Binding to an Unrestricted IP Address. The MCP Server’s HTTP listener does not properly restrict itself to the loopback interface (127.0.0.1), making it accessible from network interfaces that should not have access to the development server.
The CVSS v3.1 vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H, indicating:
- Network attack vector
- Low attack complexity
- No privileges required
- User interaction required
- High impact on confidentiality, integrity, and availability
Mitigation Recommendations
For organizations unable to immediately apply patches, Siemens recommends the following mitigations:
- Maintain strict inbound firewall policies (such as Windows Defender Firewall) blocking external traffic on port 7782, which is the default configuration on standard Windows installations
- If remote access is required, restrict traffic via a secure, authenticated channel such as a VPN or SSH tunnel rather than opening direct inbound firewall rules
- Configure the environment according to Siemens’ operational guidelines for Industrial Security
Companion Vulnerability
The advisory also disclosed CVE-2026-112137, a separate Cross-Site Request Forgery (CSRF) vulnerability in the same MCP Server component with a CVSS v3.1 score of 5.4. This vulnerability stems from improper validation of Content-Type and Origin headers on incoming HTTP requests, potentially allowing malicious web pages to trick users’ browsers into sending unauthorized requests to the local MCP Server.
Siemens published the security advisory on November 10, 2026, as version V1.0 of SSA-710379.
