APPLE-SA-2011-01-06-1 Mac OS X v10.6.6
Apple has released a security update to address CVE related to PackageKit. The update improves the handling of distribution script, which under the previous version could be susceptible to MIM attacks. Users should apply this update using the Software Update tool.
PGP WDE customers have issues after the update to 10.6.6, PGP is recommending that users hold off on the system update until PGP Corporation releases an update.
https://pgp.custhelp.com/app/answers/detail/a_id/2288/session/L3NpZC9jQlBwcHBqaw%3D%3D/sno/0