An issue was discovered in Insyde InsydeH2O kernel 5.2 before version 05.29.50, kernel 5.3 before version 05.38.50, kernel 5.4 before version 05.46.50, kernel 5.5 before version 05.54.50, kernel 5.6 before version 05.61.50, and kernel 5.7 before version 05.70.50. In VariableRuntimeDxe driver, callback function SmmCreateVariableLockList () calls CreateVariableLockListInSmm (). In CreateVariableLockListInSmm (), it uses StrSize () to get variable name size and it could lead to a buffer over-read.

An issue was discovered in Insyde InsydeH2O kernel 5.2 before version 05.29.50, kernel 5.3 before version 05.38.50, kernel 5.4 before version 05.46.50, kernel 5.5 before version 05.54.50, kernel 5.6 before version 05.61.50, and kernel 5.7 before version 05.70.50. In VariableRuntimeDxe driver, VariableServicesSetVariable () can be called by gRT>SetVariable () or the SmmSetSensitiveVariable () or SmmInternalSetVariable () from SMM. In VariableServicesSetVariable (), it uses StrSize () to get variable name size, uses StrLen () to get variable name length and uses StrCmp () to compare strings. These actions may cause a buffer over-read.