jsnjfz WebStack-Guns KaptchaController.java renderPicture path traversal

A vulnerability was found in jsnjfz WebStack-Guns 1.0. This affects the function renderPicture of the file src/main/java/com/jsnjfz/manage/modular/system/controller/KaptchaController.java. Performing a manipulation results in path traversal. It is possible to initiate the attack remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.