description: Incorrect pointer checks within the the FwBlockServiceSmm driver can allow arbitrary RAM modifications During review of the FwBlockServiceSmm driver, certain instances of SpiAccessLib could be tricked into writing 0xff to arbitrary system and SMRAM addresses. Fixed in: INTEL Purley-R: 05.21.51.0048 Whitley: 05.42.23.0066 Cedar Island: 05.42.11.0021 Eagle Stream: 05.44.25.0052 Greenlow/Greenlow-R(skylake/kabylake): Trunk Mehlow/Mehlow-R (CoffeeLake-S): Trunk Tatlow (RKL-S): Trunk Denverton: 05.10.12.0042 Snow Ridge: Trunk Graneville DE: 05.05.15.0038 Grangeville DE NS: 05.27.26.0023 Bakerville: 05.21.51.0026 Idaville: 05.44.27.0030 Whiskey Lake: Trunk Comet Lake-S: Trunk Tiger Lake H/UP3: 05.43.12.0052 Alder Lake: 05.44.23.0047 Gemini Lake: Not Affected Apollo Lake: Not Affected Elkhart Lake: 05.44.30.0018 AMD ROME: trunk MILAN: 05.36.10.0017 GENOA: 05.52.25.0006 Snowy Owl: Trunk R1000: 05.32.50.0018 R2000: 05.44.30.0005 V2000: Trunk V3000: 05.44.30.0007 Ryzen 5000: 05.44.30.0004 Embedded ROME: Trunk Embedded MILAN: Trunk Hygon Hygon #1/#2: 05.36.26.0016 Hygon #3: 05.44.26.0007 https://www.insyde.com/security-pledge/SA-2022060