The infamous Morris Worm was released in 1988; making use of known
vulnerabilities in Sendmail/finger/RSH (and weak passwords), it took out a
metric shitload of SUN-3s and 4BSD Vaxen (the author claimed that it was
accidental, but the idiot hadn't tested it on an isolated network first).
A temporary "condom" was discovered by Rich Kulawiec with "mkdir
/tmp/sh".
--
Dave Horsfall DTM (VK2KFU) "Those who don't understand security will
suffer."