Building

Basic OS X Hardening & DMA

In the course of a recent endpoint assessment, we also had a OS X 10.8 client system as a target. While we still rely on the Firewire “capability” of unlocking systems on a regular base (using this great tool), we noticed that Apple released a patch to disable Firewire DMA access whenever the system is in a locked state (e.g. with an active screensaver or no user logged in). As we test the Firewire DMA access vulnerability quite often (at least we thought so 😉 ) to prepare for demonstrations in the board room or client assessments, we were quite surprised that we must have actually missed that nice update. In order to verify the effectiveness of the patch, we ran our typical test bed and can quite happily confirm that the update successfully mitigates Firewire DMA access in locked system states.

Beside breaking into unpatched OS X client using Firewire DMA access ;-), we also noticed some lack of hardening guides related to Apples current OS X version 10.8, so we also compiled a basic checklist for OS X hardening measures which we want to share with you:
ERNW_Checklist_OSX_Hardening.pdf

Enjoy,
Matthias

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