A stack buffer overflow vulnerability discovered in AsfSecureBootDxe in Insyde InsydeH2O with kernel 5.0 through 5.5 allows attackers to run arbitrary code execution during the DXE phase.

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. 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