3 ms·

SEV is atm considered 'secure' SGX is not: https://arstechnica.com/information-technology/2020/03/hackers-can-steal-secret-data-stored-in-intels-sgx-secure-enc

• als0 6y ago
  Not at all. SEV has been broken many times and by more trivial means [1-3] [1] https://arxiv.org/pdf/1805.09604.pdf https://arxiv.org/pdf/1805.09604.pdf [2] https://regmedia.co.uk/2019/07/10/amd.pdf https://regmedia.co.uk/2019/07/10/amd.pdf [3] https://www.theregister.com/2019/06/26/amd_epyc_key_security_flaw/ https://www.theregister.com/2019/06/26/amd_epyc_key_security...
  • benlivengood 6y ago
    The two attack vectors are page table integrity and unencrypted VM state. Modifying the page tables to establish a cryptographic merkle tree would fix the first attack, and SEV-ES fixes the secrecy attack from the second paper. Unfortunately a change to page table structure may make it impossible to run unmodified kernels in the VM. I think it as impossible to prevent a hypervisor from fingerprinting what's running on a child VM; there are too many timing and power attacks to ever mitigate that, which was the attack vector on SEV-ES