Arbitrary command execution via IMAP buffer overflow in authenticate command.
https://github.com/CVEPhoenixProject/cvelist-bulk-download
https://euvd.enisa.europa.eu/vulnerability/EUVD-1999-0005
http://www.securityfocus.com/bid/130
http://sunsolve.sun.com/pub-cgi/retrieve.pl?doctype=coll&doc=secbull/177