sudo: information leak

It was found that malicious user can leak some information about arbitrary files by providing arbitrary value for INPUTRC, since the target application parses the INPUTRC file with the target user's privileges.

This kind of attack is in current version of readline limited to only timing attacks and leaks of line content matching a very particular format, but the next release will feature enhanced error reporting, making the disclosure more dangerous. It is also possible to cause segmentation fault through stack exhaustion in the target application by having INPUTRC specify a file with an $include directive for itself.

RHEL and Fedora by default include INPUTRC in /etc/sudoers, exposing this issue to users of the default sudo configuration. INPUTRC should not be included in "env_keep" at all, or else somehow restricted to non-restricted shells (ie /bin/sh, /bin/bash).