An attacker with specialized hardware and physical access to an impacted device may be able to perform a voltage fault injection attack resulting in compromise of the ASP secure boot potentially leading to arbitrary code execution. 

A side channel vulnerability on some of the AMD CPUs may allow an attacker to influence the return address prediction. This may result in speculative execution at an attacker-controlled address, potentially leading to information disclosure.

Insufficient input validation in CpmDisplayFeatureSmm may allow an attacker to corrupt SMM memory by overwriting an arbitrary bit in an attacker-controlled pointer potentially leading to arbitrary code execution in SMM.

Certain size values in firmware binary headers could trigger out of bounds reads during signature validation, leading to denial of service or potentially limited leakage of information about out-of-bounds memory contents.

Insufficient bounds checking in ASP may allow an attacker to issue a system call from a compromised ABL which may cause arbitrary memory values to be initialized to zero, potentially leading to a loss of integrity.

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.

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.

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.

Incorrect pointer checks within the the FwBlockServiceSmm driver can allow arbitrary RAM modifications During review of the FwBlockServiceSmm driver, certain instances of SpiAccessLib could be tricked into writing 0xff to arbitrary system and SMRAM addresses. Fixed in: INTEL Purley-R: 05.21.51.0048 Whitley: 05.42.23.0066 Cedar Island: 05.42.11.0021 Eagle Stream: 05.44.25.0052 Greenlow/Greenlow-R(skylake/kabylake): Trunk Mehlow/Mehlow-R (CoffeeLake-S): Trunk Tatlow (RKL-S): Trunk Denverton: 05.10.12.0042 Snow Ridge: Trunk Graneville DE: 05.05.15.0038 Grangeville DE NS: 05.27.26.0023 Bakerville: 05.21.51.0026 Idaville: 05.44.27.0030 Whiskey Lake: Trunk Comet Lake-S: Trunk Tiger Lake H/UP3: 05.43.12.0052 Alder Lake: 05.44.23.0047 Gemini Lake: Not Affected Apollo Lake: Not Affected Elkhart Lake: 05.44.30.0018 AMD ROME: trunk MILAN: 05.36.10.0017 GENOA: 05.52.25.0006 Snowy Owl: Trunk R1000: 05.32.50.0018 R2000: 05.44.30.0005 V2000: Trunk V3000: 05.44.30.0007 Ryzen 5000: 05.44.30.0004 Embed…