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.

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.

Improper validation of the BIOS directory may allow for searches to read beyond the directory table copy in RAM, exposing out of bounds memory contents, resulting in a potential denial of service.

Insufficient bound checks in the System Management Unit (SMU) may result in access to an invalid address space that could result in denial of service.

Insufficient checks in System Management Unit (SMU) FeatureConfig may result in reenabling features potentially resulting in denial of resources and/or denial of service.

Insufficient General Purpose IO (GPIO) bounds check in System Management Unit (SMU) may result in access/updates from/to invalid address space that could result in denial of service.

Insufficient bound checks in the System Management Unit (SMU) may result in a system voltage malfunction that could result in denial of resources and/or possibly denial of service.

Insufficient bound checks related to PCIE in the System Management Unit (SMU) may result in access to an invalid address space that could result in denial of service.

Insufficient bounds checking in an SMU mailbox register could allow an attacker to potentially read outside of the SRAM address range which could result in an exception handling leading to a potential denial of service.

A TOCTOU race condition in SMU may allow for the caller to obtain and manipulate the address of a message port register which may result in a potential denial of service.

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.

Insufficient validation of addresses in AMD Secure Processor (ASP) firmware system call may potentially lead to arbitrary code execution by a compromised user application.

Improper validation of destination address in SVC_LOAD_FW_IMAGE_BY_INSTANCE and SVC_LOAD_BINARY_BY_ATTRIB in a malicious UApp or ABL may allow an attacker to overwrite arbitrary bootloader memory with SPI ROM contents resulting in a loss of integrity and availability.

Failure to validate inputs in SMM may allow an attacker to create a mishandled error leaving the DRTM UApp in a partially initialized state potentially resulting in loss of memory integrity.

Failure to verify SEV-ES TMR is not in MMIO space, SEV-ES FW could result in a potential loss of integrity or availability.