A flaw was found in hw. Mis-trained branch predictions for return instructions may allow arbitrary speculative code execution under certain microarchitecture-dependent conditions.

A flaw was found in hw. Aliases in the branch predictor may cause some AMD processors to predict the wrong branch type, potentially leading to information disclosure.

Improper initialization of variables in the DXE driver may allow a privileged user to leak sensitive information via local access.

Improper initialization of variables in the DXE driver may allow a privileged user to leak sensitive information via local access.

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.

Insufficient control flow management in AmdCpmGpioInitSmm may allow a privileged attacker to tamper with the SMM handler potentially leading to escalation of privileges.

Insufficient control flow management in AmdCpmOemSmm may allow a privileged attacker to tamper with the SMM handler potentially leading to an escalation of privileges.

Insufficient DRAM address validation in System Management Unit (SMU) may allow an attacker to read/write from/to an invalid DRAM address, potentially resulting in denial-of-service.

A potential vulnerability in some AMD processors using frequency scaling may allow an authenticated attacker to execute a timing attack to potentially enable information disclosure.

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.