nmh
nmh (new MH) is a powerful electronic mail handling system. It was originally based on version 6.8.3 of the MH message system developed by the RAND Corporation and the University of California. It is intended to be a (mostly) compatible drop-in replacement for MH. nmh consists of a collection of fairly simple single-purpose programs to send, receive, save, retrieve, and manipulate e-mail messages. Since nmh is a suite rather than a single monolithic program, you may freely intersperse nmh commands with other commands at your shell prompt, or write custom scripts which use these commands in flexible ways. NOTE: All versions of nmh prior to 1.0.3 (as well as MH) contained a vulnerability where incoming mail messages with carefully designed MIME headers could cause the mhshow command to execute arbitrary shell code. Though the authors of nmh are not aware of any exploits of this hole, MH users and users of older versions of nmh are strongly encouraged to upgrade to the current version.