Alas, CPU. Namely ME[1] and FSP&#x2F;SMM blob [2].<p>If you are wondering what&#x27;s wrong with either of them, I would recommend Joanna Rutkowska&#x27;s research as a starting point [3,4].<p>[1] <a href="https:&#x2F;&#x2F;libreboot.org&#x2F;faq&#x2F;#intelme" rel="nofollow">https:&#x2F;&#x2F;libreboot.org&#x2F;faq&#x2F;#intelme</a><p>[2] <a href="https:&#x2F;&#x2F;libreboot.org&#x2F;faq&#x2F;#fsp" rel="nofollow">https:&#x2F;&#x2F;libreboot.org&#x2F;faq&#x2F;#fsp</a><p>[3] <a href="http:&#x2F;&#x2F;blog.invisiblethings.org&#x2F;papers&#x2F;2015&#x2F;x86_harmful.pdf" rel="nofollow">http:&#x2F;&#x2F;blog.invisiblethings.org&#x2F;papers&#x2F;2015&#x2F;x86_harmful.pdf</a><p>[4] <a href="https:&#x2F;&#x2F;media.ccc.de&#x2F;v&#x2F;32c3-7352-towards_reasonably_trustworthy_x86_laptops" rel="nofollow">https:&#x2F;&#x2F;media.ccc.de&#x2F;v&#x2F;32c3-7352-towards_reasonably_trustwor...</a>