COMMAND
/lib/bugfiler
SYSTEMS AFFECTED
AIX 3.x
PROBLEM
Johannes Schwabe posted following. bugfiler is intended to be
run from a mail alias, handle bug reports piped to it, and
maintain a database of bug reports in the specified directory.
Local users can circumvent file access restrictions, leading to
increased privileges. Depending on the installation of the
system, root privileges may be gained. Exploit:
$whoami
eviluser
$/lib/bugfiler -b <user> <directory>
This creates funny files under the <user>-owned <directory> and
that may be used by crackers to increase privileges. See the
manpage of bugfiler for more information. (bugfiler does not
work for some <user>s)
SOLUTION
There should be no need for mere mortals executing it, and it
should be prevented that local users run it. On systems not using
bugfiler at all, the suggestion for the admin is to simply remove
the SUID bit from all bugfiler binaries. (The actual fix may
differ from system to system.)
Mail from "<bugs@...> (Bugs Bunny)" may mean that /lib/bugfiler
was executed.