All Your Secrets Belong to Us: Leveraging Firmware Bugs to Break TEEs

Modern TEEs depend on highly privileged firmware to securely implement complex features, coordinate between different hardware components, and provide a root of trust. Parts of AMD's SEV-SNP technology are implemented in firmware running on the Platform Security Processor.
This talk details two vulnerabilities in this firmware and presents novel techniques to exploit such vulnerabilities. This results in a complete loss of confidentiality, as an attacker can decrypt arbitrary guest memory on affected systems. In some cases, an attacker can arbitrarily change the contents of encrypted memory leading to a complete loss of integrity of a running guest.
By:
Tom Dohrmann | Security Researcher
Full Abstract and Presentation Materials:
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