Revision Note: V1.1 (June 10, 2014): Advisory revised to announce a detection change for the update rollup (updates 2920189 and 2961908). This is a detection change only. There were no changes to the update files. Customers who have already successfully updated their systems do not need to take any action. Summary: With this advisory, Microsoft is revoking the digital signature for four private, third-party UEFI (Unified Extensible Firmware Interface) modules that could be loaded during UEFI Secure Boot.