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I hope that they provide a visible warning that secure boot is subverted. So it's not that some evil maid could replace the boot chain and update the firmware

I hope that they provide a visible warning that secure boot is subverted. So it's not that some evil maid could replace the boot chain and update the firmware settings to make it behave as if nothing happened. Just for those folks who use and want it. And maybe also introduce a TOFU model i.e. "allow execute" but ask when the hash changes, so booting the same unsigned binary is OK but updates aren't silently allowed and require a quick confirmation (possibly with a timer for unattended reboots). Won't help against physical attacker but should help against a malware that manages to get root and tries to install itself into the boot chain.

stefan_ 4y ago
So the maid replaces your keyboard instead. There is no security in this scenario, the only option is "don't use the computer". Meanwhile, there is a really weird segment of "security people" that focus a whole lot about attestation and signatures and "secure boot" and the like but very little about what actually ends up breaking systems. Call it the Sony syndrome where you ship 15 layers of chainloaded bootloaders and security systems but don't bother updating the years old WebKit. Apple has it too, always money around for implementing another mitigation scheme in XNU but if you ask why nobody updated the outdated open-source PDF library embedded in their Objective C messaging program it's crickets.
- drdaeman 4y ago
  > So the maid replaces your keyboard instead Well, it's another level of sophistication, requiring some more investment? Replacing a bootloader or a kernel (or initrd) and disabling Secure Boot is easy for just about anyone with 5-10 minutes access to a machine. A modified keyboard is less so.
  - userbinator 4y ago
    Less than a minute is enough to install a hardware inline keylogger. IMHO if you're truly worthy enough to be targeted by such attacks, "secure" boot isn't going to stop them.
    - deleted 4y ago
      [deleted]
  - smileybarry 4y ago
    Then you set an administrator password in your BIOS and prevent changes by anyone but you. Some laptops even allow you to use the fingerprint reader for this. (Had a ThinkPad that did this)

stefan_ 4y ago

So the maid replaces your keyboard instead. There is no security in this scenario, the only option is "don't use the computer". Meanwhile, there is a really weird segment of "security people" that focus a whole lot about attestation and signatures and "secure boot" and the like but very little about what actually ends up breaking systems. Call it the Sony syndrome where you ship 15 layers of chainloaded bootloaders and security systems but don't bother updating the years old WebKit. Apple has it too, always money around for implementing another mitigation scheme in XNU but if you ask why nobody updated the outdated open-source PDF library embedded in their Objective C messaging program it's crickets.

drdaeman 4y ago
> So the maid replaces your keyboard instead Well, it's another level of sophistication, requiring some more investment? Replacing a bootloader or a kernel (or initrd) and disabling Secure Boot is easy for just about anyone with 5-10 minutes access to a machine. A modified keyboard is less so.
- userbinator 4y ago
  Less than a minute is enough to install a hardware inline keylogger. IMHO if you're truly worthy enough to be targeted by such attacks, "secure" boot isn't going to stop them.
  - deleted 4y ago
    [deleted]
- smileybarry 4y ago
  Then you set an administrator password in your BIOS and prevent changes by anyone but you. Some laptops even allow you to use the fingerprint reader for this. (Had a ThinkPad that did this)