Insufficient input validation in the SMU may allow a physical attacker to exfiltrate SMU memory contents over the I2C bus potentially leading to a loss of confidentiality.

Improper syscall input validation in the ASP Bootloader may allow a privileged attacker to read memory out-of-bounds, potentially leading to a denial-of-service.

Insufficient syscall input validation in the ASP Bootloader may allow a privileged attacker to read memory outside the bounds of a mapped register potentially leading to a denial of service.

TOCTOU in the ASP may allow a physical attacker to write beyond the buffer bounds, potentially leading to a loss of integrity or denial of service.

Improper input validation and bounds checking in SEV firmware may leak scratch buffer bytes leading to potential information disclosure.

Insufficient bounds checking in ASP (AMD Secure Processor) firmware while handling BIOS mailbox commands, may allow an attacker to write partially-controlled data out-of-bounds to SMM or SEV-ES regions which may lead to a potential loss of integrity and availability.

Insufficient input validation in SYS_KEY_DERIVE system call in a compromised user application or ABL may allow an attacker to corrupt ASP (AMD Secure Processor) OS memory which may lead to potential arbitrary code execution.

Insufficient validation of address mapping to IO in ASP (AMD Secure Processor) may result in a loss of memory integrity in the SNP guest.

Insufficient fencing and checks in System Management Unit (SMU) may result in access to invalid message port registers that could result in a potential denial-of-service.

Insufficient validation in ASP BIOS and DRTM commands may allow malicious supervisor x86 software to disclose the contents of sensitive memory which may result in information disclosure.

Failure to verify the mode of CPU execution at the time of SNP_INIT may lead to a potential loss of memory integrity for SNP guests.

Failure to validate the communication buffer and communication service in the BIOS may allow an attacker to tamper with the buffer resulting in potential SMM (System Management Mode) arbitrary code execution.

IBPB may not prevent return branch predictions from being specified by pre-IBPB branch targets leading to a potential information disclosure.

Execution unit scheduler contention may lead to a side channel vulnerability found on AMD CPU microarchitectures codenamed “Zen 1”, “Zen 2” and “Zen 3” that use simultaneous multithreading (SMT). By measuring the contention level on scheduler queues an attacker may potentially leak sensitive information.

An attacker with access to a malicious hypervisor may be able to infer data values used in a SEV guest on AMD CPUs by monitoring ciphertext values over time.

Failure to assign a new report ID to an imported guest may potentially result in an SEV-SNP guest VM being tricked into trusting a dishonest Migration Agent (MA).

Failure to flush the Translation Lookaside Buffer (TLB) of the I/O memory management unit (IOMMU) may lead an IO device to write to memory it should not be able to access, resulting in a potential loss of integrity.

Failure to validate the integer operand in ASP (AMD Secure Processor) bootloader may allow an attacker to introduce an integer overflow in the L2 directory table in SPI flash resulting in a potential denial of service.

In SEV guest VMs, the CPU may fail to flush the Translation Lookaside Buffer (TLB) following a particular sequence of operations that includes creation of a new virtual machine control block (VMCB). The failure to flush the TLB may cause the microcode to use stale TLB translations which may allow for disclosure of SEV guest memory contents. Users of SEV-ES/SEV-SNP guest VMs are not impacted by this vulnerability.

A bug in AMD CPU’s core logic may allow for an attacker, using specific code from an unprivileged VM, to trigger a CPU core hang resulting in a potential denial of service. AMD believes the specific code includes a specific x86 instruction sequence that would not be generated by compilers.