CUPS 1.4.4, when running in certain Linux distributions such as Debian GNU/Linux, stores the web interface administrator key in /var/run/cups/certs/0 using certain permissions, which allows local users in the lpadmin group to read or write arbitrary files as root by leveraging the web interface.
file/show.cgi in Webmin 1.590 and earlier allows remote authenticated users to execute arbitrary commands via an invalid character in a pathname, as demonstrated by a | (pipe) character.
