(RHSA-2010:0457) Moderate: perl security update

Perl is a high-level programming language commonly used for system
administration utilities and web programming. The Safe extension module
allows users to compile and execute Perl code in restricted compartments.

The Safe module did not properly restrict the code of implicitly called
methods (such as DESTROY and AUTOLOAD) on implicitly blessed objects
returned as a result of unsafe code evaluation. These methods could have
been executed unrestricted by Safe when such objects were accessed or
destroyed. A specially-crafted Perl script executed inside of a Safe
compartment could use this flaw to bypass intended Safe module
restrictions. (CVE-2010-1168)

The Safe module did not properly restrict code compiled in a Safe
compartment and executed out of the compartment via a subroutine reference
returned as a result of unsafe code evaluation. A specially-crafted Perl
script executed inside of a Safe compartment could use this flaw to bypass
intended Safe module restrictions, if the returned subroutine reference was
called from outside of the compartment. (CVE-2010-1447)

Red Hat would like to thank Tim Bunce for responsibly reporting the
CVE-2010-1168 and CVE-2010-1447 issues. Upstream acknowledges Nick Cleaton
as the original reporter of CVE-2010-1168, and Tim Bunce and Rafaël
Garcia-Suarez as the original reporters of CVE-2010-1447.

These packages upgrade the Safe extension module to version 2.27. Refer to
the Safe module’s Changes file, linked to in the References, for a full
list of changes.

Users of perl are advised to upgrade to these updated packages, which
correct these issues. All applications using the Safe extension module must
be restarted for this update to take effect.