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.

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