hw: amd: arbitrary code execution in bios due to a fault in communication buffer

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.

hw: cpu: AMD: Execution Unit Scheduler Contention Side-Channel vulnerability

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.

A malicious or compromised UApp or ABL may be used by an attacker to send a malformed system call to the bootloader, resulting in out-of-bounds memory accesses.

An attacker, who gained elevated privileges via some other vulnerability, may be able to read data from Boot ROM resulting in a loss of system integrity.

A malicious or compromised UApp or ABL may be used by an attacker to issue a malformed system call which results in mapping sensitive System Management Network (SMN) registers leading to a loss of integrity and availability.

A malicious or compromised User Application (UApp) or AGESA Boot Loader (ABL) could be used by an attacker to exfiltrate arbitrary memory from the ASP stage 2 bootloader potentially leading to information disclosure.

Failure to verify the protocol in SMM may allow an attacker to control the protocol and modify SPI flash resulting in a potential arbitrary code execution.

hw: amd: Spectre based on Linear Address Masking

When combined with specific software sequences, AMD CPUs may transiently execute non-canonical loads and store using only the lower 48 address bits potentially resulting in data leakage.