Comment by metalcrow

1 day ago

That's fair, although aren't most TPMs nowadays fTPMs? No interceptable communication that way.

Until they require fTPMs, an attacker can just choose to use a regular TPM.

A more sophisticated attacker could plausibly extract key material from the TPM itself via sidechannels, and sign their own attestations.

  • I remember there's a PCI device that's meant to be snooping and manipulating RAM directly by using DMA. Pretty much one computer runs the game and one computer runs the cheat. I think kernel anti cheats are just raising the bar while pretty much being too intrusive

    • TFA explicitly describes those devices, and how anti-cheat developers are trying to handle this.

      But the main point there is that this setup is prohibitively expensive for most cheaters.

Can a TPM be faked in a QEMU VM?

  • Technically yes, but it would produce an untrusted remote attestation signature (quote). This is roughly equivalent to using TLS with a self-signed certificate — it’s not trusted by anyone else. TPMs have a signing key that’s endorsed by the TPM vendor’s CA.

  • We don't allow games to run in virtual machines and require TPM. Check TPM EK signing up to an approved manufacturer.

    It is not "fake", a software TPM is real TPM but not accepted/approved by anticheat due to inability to prove its provenance

    (Disclosure: I am not on the team that works on Vanguard, I do not make these decisions, I personally would like to play on my framework laptop)