CVE-2026-40075: OpenMRS ModuleResourcesServlet has Path Traversal that Leads to Arbitrary File Read

The /openmrs/moduleResources/{moduleid} endpoint in OpenMRS Core is vulnerable to a path traversal attack. The ModuleResourcesServlet does not properly validate user-supplied path input, allowing an attacker to traverse directories and read arbitrary files from the server filesystem (e.g., /etc/passwd, application configuration files containing database credentials).

This endpoint serves static module resources (CSS, JS, images) and is not protected by authentication filters, as these resources are required for rendering the login page. Therefore, this vulnerability can be exploited by an unauthenticated attacker.

Note: Successful exploitation requires the target deployment to run on Apache Tomcat < 8.5.31, where the ..; path parameter bypass is not mitigated by the container. Deployments on Tomcat ≥ 8.5.31 / ≥ 9.0.10 are protected at the container level, though the underlying code defect remains.