John Butterworth

The issue is related to an integer overflow in the Drive Execution Environment (DXE) phase in the Capsule Update feature in the UEFI implementation. This allows physically proximate attackers to bypass intended access restrictions via crafted data.

The issue concerns multiple integer overflows in the Pre-EFI Initialization (PEI) boot phase in the Capsule Update feature in the UEFI implementation. This allows physically proximate attackers to bypass intended access restrictions by providing crafted data that is not properly handled during the coalescing phase.

The issue is related to errors in the code of the EFI module in Mac OS X, which can be exploited by a remote attacker to access undeclared functions. The vulnerability is caused by the mishandling of arguments, allowing attackers to reach unused functions via unspecified vectors.

The BIOS implementation does not enforce a BIOS CNTL locking protection mechanism upon being woken from sleep, allowing local users to conduct EFI flash attacks by leveraging console access.

The issue allows local users to bypass intended BIOS signing requirements and install arbitrary BIOS images by leveraging administrative privileges. This is achieved by providing a crafted `rbu packet.pktNum` value in conjunction with a crafted `rbu packet.pktSize` value, exploiting a buffer overflow in the Dell BIOS.