A side channel attack known as ‘Inception’ or ‘RAS Poisoning’ may allow an attacker to influence branch prediction, potentially leading to information disclosure.

Refer: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7005.html

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

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.

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.

Improper Access Control in the AMD SPI protection feature may allow a user with Ring0 (kernel mode) privileged access to bypass protections potentially resulting in loss of integrity and availability.

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 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 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.

Insufficient protections in System Management Mode (SMM) code may allow an attacker to potentially enable escalation of privilege via local access.

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.

A malicious or compromised UApp or ABL could potentially change the value that the ASP uses for its reserved DRAM, to one outside of the fenced area, potentially leading to data exposure.

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.

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.

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.

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.

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 malformed SMI (System Management Interface) command may allow an attacker to establish a corrupted SMI Trigger Info data structure, potentially leading to out-of-bounds memory reads and writes when triggering an SMI resulting in a potential loss of resources.

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.

An attacker with root account privileges can load any legitimately signed firmware image into the Audio Co-Processor (ACP,) irrespective of the respective signing key being declared as usable for authenticating an ACP firmware image, potentially resulting in a denial of service.

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.

A flaw was found in hw. This issue can cause AMD CPUs to transiently execute beyond unconditional direct branches.

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.

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.