An issue was discovered in Kernel 5.x in Insyde InsydeH2O, affecting HddPassword. Software SMI services that use the Communicate() function of the EFI_SMM_COMMUNICATION_PROTOCOL do not check whether the address of the buffer is valid, which allows use of SMRAM, MMIO, or OS kernel addresses.
https://www.insyde.com/security-pledge/SA-2022014
https://www.insyde.com/security-pledge
https://security.netapp.com/advisory/ntap-20220222-0004/
https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf