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I still use BIOS and I hopefully never be forced to use UEFI or Secure Boot. Again RMS and Theo both came out against UEFI (IIRC). But $ mean more in security
by jmclnx 3y ago
I still use BIOS and I hopefully never be forced to use UEFI or Secure Boot. Again RMS and Theo both came out against UEFI (IIRC). But $ mean more in security.
> that have lurked for years, if not decades, in Unified Extensible Firmware Interfaces responsible for booting modern devices that run Windows or Linux
What does this mean, "decades" ?? I kind of doubt it. I guess we cannot have a article without sensationalism.
- yjftsjthsd-h 3y agoIf BIOS is immune to this, it's only by coincidence; there's no reason to think older firmware that allows the user to set the boot logo isn't equally riddled with vulnerabilities.
- jmclnx 3y agoLast I heard, BIOS firmware is forced to be 64k (or 128k), but that limit could have changed over the years. Not much of a logo would fit with that limit. edit: just checked, the BIOS in my newest laptop ~10 years old is 128k. But the ROM size is 12M which is interesting. I can enable UEFI so I can only guess the remaining space is used for that.
- yjftsjthsd-h 3y agoI mean, I don't know how it's stored, but it does still have a boot logo. I guess if it only supports really tiny logo files for whatever reason that reduces the amount of code an attacker can give it, but that doesn't feel like a very good defense. Edit: Oh, or if the older firmwares only supported a logo that was hardcoded into the image and that can't be updated separately, that might help. Still coincidental, though; you certainly could have a user-controlled logo with BIOS, and as the article notes, there are UEFI implementations that also hardcode the logo.
- p_l 3y agoIn reality you have UEFI and the 128k is 16bit shim code of the Compatibility Support Module that emulates BIOS interfaces. UEFI Class 1 devices (which had hardcoded CSM and didn't allow access to UEFI APIs from bootloader or OS) started shipping as early as 2005 - because it made it much simpler to build firmware especially when you're supposed to integrate complex vendor specific code (for example from Intel). Even before that, it was not uncommon for BIOS to actually be much bigger than 128k. Logos were also common as part of BIOS. Hell, 1990s had a bunch of BIOSes with GUIs with mouse support. Some even tried to emulate look&feel of Windows. At least UEFI provides a graphics toolkit that supports rendering to both GUI and serial port, so you don't have to deal with BIOSes that can't be connected to over serial because they need VGA raster output...
- mr_toad 3y agoThis was true in 8086 machines, but it was extended in various ways. https://stackoverflow.com/questions/56216128/how-can-the-bios-larger-than-64kb-today https://stackoverflow.com/questions/56216128/how-can-the-bio...
- iwontberude 3y agoPCBIOS is just a compatibility mode for UEFI chipsets now, so there is no avoiding it -- sorry :(
- anticensor 3y agox86s is going to be UEFI only and amd64 only: https://www.intel.com/content/www/us/en/developer/articles/technical/envisioning-future-simplified-architecture.html https://www.intel.com/content/www/us/en/developer/articles/t...
- dist-epoch 3y agoAll computers newer than 10 years are based on UEFI. Which exposes a BIOS emulation layer: CSM (Compatibility Support Module)
- Nullabillity 3y agoIf "running OS can cause the computer to load unsigned code" is something you care about, BIOS is already "vulnerable", by virtue of not even trying to prevent it.