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Technology & Policy

Articles from March 2015

2015 (Jan, Mar, May, Oct), 2016, 2017

Lenovo ThinkPad HDD Password

by Jethro Beekman – Mar 8, 2015 . Filed under: English, Technology, Security, Lenovo ThinkPad.

Modern SSDs (at least the ones made by Intel, Samsung) always encrypt all stored data using AES. The encryption key used is stored in nonvolatile memory on the SSD. One of the reasons for this is that to securely wipe the drive now you just need to overwrite the encryption key with a new random one. This way, you don’t need to erase every flash block, which is very bad for durability reasons. The encryption key can optionally be encrypted using a 32-byte “security password”, the configuration of which is overloaded on the ATA security feature set. If you trust the hardware manufacturer to actually implement this securely, this would seem to provide a very solid and fast option for encrypted persistent storage. Continue reading…Comments

Reverse Engineering UEFI Firmware

by Jethro Beekman – Mar 8, 2015 . Filed under: English, Technology, UEFI, Reverse Engineering.

In order to figure out how my BIOS drive password worked, I had to reverse-engineer the firmware that comes with my laptop. You can find the binary blobs on the update CD that Lenovo provides, and it turns out these blobs are actually UEFI images. UEFI firmware is made up of many different loadable modules (drivers, shared libraries, etc.), which are stored in the Portable Executable (PE) image format. These modules can be extracted from the image using Nikolaj Schlej’s excellent UEFIExtract (from UEFITool). Once you have all the PE modules, the real reversing can begin. Continue reading…Comments