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.

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2026-40075 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.8.6); upgrading removes the vulnerable code path.

Kodem intelligence

Add a path boundary check after constructing realPath and before returning the File object. The fix should use normalize() + startsWith() to ensure the resolved path stays within the allowed module resources directory:

File f = new File(realPath);
Path allowedBase = Paths.get(getServletContext().getRealPath(""), "WEB-INF", "view", "module");
if (!f.toPath().normalize().startsWith(allowedBase.normalize())) {
    log.warn("Blocked path traversal attempt: {}", request.getPathInfo());
    return null;
}

This is consistent with the existing pattern used in StartupFilter.java and TestInstallUtil.java within the same project.

1. What is CVE-2026-40075? CVE-2026-40075 is a high-severity path traversal vulnerability in org.openmrs.web:openmrs-web (maven), affecting versions <= 2.7.8. It is fixed in 2.8.6. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2026-40075? CVE-2026-40075 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of org.openmrs.web:openmrs-web are affected by CVE-2026-40075? org.openmrs.web:openmrs-web (maven) versions <= 2.7.8 is affected.
4. Is there a fix for CVE-2026-40075? Yes. CVE-2026-40075 is fixed in 2.8.6. Upgrade to this version or later.
5. Is CVE-2026-40075 exploitable, and should I be worried? Whether CVE-2026-40075 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-40075 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-40075? Upgrade org.openmrs.web:openmrs-web to 2.8.6 or later.