The ntpq saveconfig command does not do adequate filtering of special characters from the supplied filename. Note: the ability to use the saveconfig command is controlled by the 'restrict nomodify' directive, and the recommended default configuration is to disable this capability. If the ability to execute a 'saveconfig' is required, it can easily (and should) be limited and restricted to a known small number of IP addresses. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-7976