GNU Libtool is a set of shell scripts which automatically configure UNIX, Linux, and similar operating systems to generically build shared libraries.
A flaw was found in the way GNU Libtool's libltdl library looked for modules to load. It was possible for libltdl to load and run modules from an arbitrary library in the current working directory. If a local attacker could trick a local user into running an application (which uses libltdl) from an attacker-controlled directory containing a malicious Libtool control file (.la), the attacker could possibly execute arbitrary code with the privileges of the user running the application. (CVE-2009-3736)
All libtool users should upgrade to these updated packages, which contain a backported patch to correct this issue. After installing the updated packages, applications using the libltdl library must be restarted for the update to take effect.