openHAB, a provider of open-source home automation software, has add-ons including the visualization add-on CometVisu. CometVisuServlet in versions prior to 4.2.1 is susceptible to an unauthenticated path traversal vulnerability. Local files on the server can be requested via HTTP GET on the CometVisuServlet. This issue may lead to information disclosure. Users should upgrade to version 4.2.1 of the CometVisu add-on of openHAB to receive a patch.