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.

An issue was discovered in IhisiSmm in Insyde InsydeH2O with kernel 5.0 through 5.5. It is possible to write to an attacker-controlled address. An attacker could invoke an SMI handler with a malformed pointer in RCX that overlaps SMRAM, resulting in SMM memory corruption.

An issue was discovered in ChipsetSvcSmm in Insyde InsydeH2O with kernel 5.0 through 5.5. There is insufficient input validation in BIOS Guard updates. An attacker can induce memory corruption in SMM by supplying malformed inputs to the BIOS Guard SMI handler.