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. When SMT is enabled, certain AMD processors may speculatively execute instructions using a target from the sibling thread after an SMT mode switch potentially resulting in information disclosure.

References: https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1045 https://www.openwall.com/lists/oss-security/2023/02/14/4 https://xenbits.xen.org/xsa/advisory-426.html https://kernel.org/doc/html//next/admin-guide/hw-vuln/cross-thread-rsb.html

AMD Ryzen, Gen AMD EPYC Processors could allow a local authenticated attacker to obtain sensitive information, caused by a use-after-free flaw in the vzeroupper instruction. By conducting a cache timing attack using a specially crafted application, an attacker could exploit this vulnerability to obtain sensitive data used by other processes, such as passwords and encryption keys, at a rate of 30KB/sec from each CPU core.

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.

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.

A TOCTOU in ASP bootloader may allow an attacker to tamper with the SPI ROM following data read to memory potentially resulting in S3 data corruption and information disclosure.

A compromised or malicious ABL or UApp could send a SHA256 system call to the bootloader, which may result in exposure of ASP memory to userspace, potentially leading to information disclosure.

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.

Improper access control in System Management Mode (SMM) may allow an attacker to write to SPI ROM potentially leading to arbitrary code execution.

A flaw was found in hw. The speculative execution window of AMD LFENCE/JMP mitigation (MITIGATION V2-2) may be large enough to be exploited on AMD CPUs.

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.

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.

Insufficient DRAM address validation in System Management Unit (SMU) may result in a DMA read from invalid DRAM address to SRAM resulting in SMU not servicing further requests.

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.

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.

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

Improper parameters handling in the AMD Secure Processor (ASP) kernel may allow a privileged attacker to elevate their privileges potentially leading to loss of integrity.

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.

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.

Improper parameters handling in AMD Secure Processor (ASP) drivers may allow a privileged attacker to elevate their privileges potentially leading to loss of integrity.

A malicious or compromised UApp or ABL may coerce the bootloader into corrupting arbitrary memory potentially leading to loss of integrity of data.

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 DRAM address validation in System Management Unit (SMU) may result in a DMA (Direct Memory Access) read/write from/to invalid DRAM address that could result in denial of service.

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.

Insufficient check of the process type in Trusted OS (TOS) may allow an attacker with privileges to enable a lesser privileged process to unmap memory owned by a higher privileged process resulting in a denial of service.

Insufficient verification of missing size check in 'LoadModule' may lead to an out-of-bounds write potentially allowing an attacker with privileges to gain code execution of the OS/kernel by loading a malicious TA.