Impact

Arbitrary file exfiltration due to failure to sanitize request when satisfying GET requests for /images & /initfilter/scripts. This can allow an attacker to access any file on a system running OpenMRS that is accessible to the user id OpenMRS is running under.

Vulnerability location:

• https://lgtm.com/projects/g/openmrs/openmrs-core/snapshot/fb1335c925ca4c94be5a546707b90d2c1efa4dcc/files/web/src/main/java/org/openmrs/web/filter/StartupFilter.java#L123

• openmrs-core/web/src/main/java/org/openmrs/web/filter/StartupFilter.java

  Line 123 in ee3373a

  file = new File(file, httpRequest.getPathInfo());

			if (servletPath.startsWith("/images") || servletPath.startsWith("/initfilter/scripts")) {
				servletPath = servletPath.replaceFirst("/initfilter", "/WEB-INF/view"); // strip out the /initfilter part
				// writes the actual image file path to the response
				File file = new File(filterConfig.getServletContext().getRealPath(servletPath));
				if (httpRequest.getPathInfo() != null) {
					file = new File(file, httpRequest.getPathInfo()); // VULNERABILITY: `httpRequest.getPathInfo()` is user controlled and can contain `../../..` path traversal payloads
				}
				
				InputStream imageFileInputStream = null;
				try {
					imageFileInputStream = new FileInputStream(file);
					OpenmrsUtil.copyFile(imageFileInputStream, httpResponse.getOutputStream()); // VULNERABILITY: Attacker controlled path file is returned
				}

Patches

Affected implementations should update to the latest patch version of OpenMRS Core for the minor version they use. These are:

• 2.1.5
• 2.2.1
• 2.3.5
• 2.4.5
• 2.5.3

Patch that fixes this vulnerability can be found here: db8454b#diff-7c64d9f61d4d4e2ddba92920d7cf63ec96091b308d43904956b3846bc0c26d80R128

Workarounds and Mitigation

As a general rule, this vulnerability is already mitigated by Tomcat's URL normalization in Tomcat 7.0.28+. Implementers on older versions of Tomcat should consider upgrading their Tomcat instance as well as their OpenMRS instance.

For more information

If you have any questions or comments about this advisory:

• Email us at [email protected]