Paul Ling has found a security flaw in the file-local
variables code in GNU Emacs.
When the Emacs user option `enable-local-variables' is
set to `:safe' (the default value is t), Emacs should
automatically refuse to evaluate `eval' forms in file-local
variable sections. Due to the bug, Emacs instead
automatically evaluates such `eval' forms. Thus, if the user
changes the value of `enable-local-variables' to `:safe',
visiting a malicious file can cause automatic execution of
arbitrary Emacs Lisp code with the permissions of the
user.
The bug is present in Emacs 23.2, 23.3, 23.4, and
24.1.