Emacs 21.2.1 does not prompt or warn the user before executing Lisp code in the local variables section of a text file, which allows user-assisted attackers to execute arbitrary commands, as demonstrated using the mode-name variable.
http://www.securityfocus.com/bid/15375
http://www.mandriva.com/security/advisories?name=MDKSA-2005:208
http://secunia.com/advisories/17496
http://lists.grok.org.uk/pipermail/full-disclosure/2003-May/005089.html