CVE-2017-9386: Improper Limitation of a Pathname to a Restricted Directory

An issue was discovered on Vera VeraEdge 1.7.19 and Veralite 1.7.481 devices. The device provides a script file called "get_file.sh" which allows a user to retrieve any file stored in the "cmh-ext" folder on the device. However, the "filename" parameter is not validated correctly and this allows an attacker to directory traverse outside the /cmh-ext folder and read any file on the device. It is necessary to create the folder "cmh-ext" on the device which can be executed by an attacker first in an unauthenticated fashion and then execute a directory traversal attack.