system-config-firewall is a graphical user interface for basic firewall
setup.
It was found that system-config-firewall used the Python pickle module in
an insecure way when sending data (via D-Bus) to the privileged back-end
mechanism. A local user authorized to configure firewall rules using
system-config-firewall could use this flaw to execute arbitrary code with
root privileges, by sending a specially-crafted serialized object.
(CVE-2011-2520)
Red Hat would like to thank Marco Slaviero of SensePost for reporting this
issue.
This erratum updates system-config-firewall to use JSON (JavaScript Object
Notation) for data exchange, instead of pickle. Therefore, an updated
version of system-config-printer that uses this new communication data
format is also provided in this erratum.
Users of system-config-firewall are advised to upgrade to these updated
packages, which contain a backported patch to resolve this issue. Running
instances of system-config-firewall must be restarted before the utility
will be able to communicate with its updated back-end.