{"cve":"CVE-2021-33627","nvd":{"published":"2022-02-03T02:15:06.983","modified":"2026-08-11T13:17:19.790","status":"Modified","description":"An issue was discovered in Insyde InsydeH2O Kernel 5.0 before 05.09.11, 5.1 before 05.17.11, 5.2 before 05.27.11, 5.3 before 05.36.11, 5.4 before 05.44.11, and 5.5 before 05.52.11 affecting FwBlockServiceSmm. 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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H","score":8.2},"cwes":["CWE-119"],"references":["https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf","https://security.netapp.com/advisory/ntap-20220222-0002/","https://www.insyde.com/security-pledge","https://www.insyde.com/security-pledge/SA-2022022","https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf"],"products":["insyde:insydeh2o","siemens:simatic_field_pg_m5_firmware","siemens:simatic_field_pg_m6_firmware","siemens:simatic_ipc127e_firmware","siemens:simatic_ipc227g_firmware","siemens:simatic_ipc277g_firmware","siemens:simatic_ipc327g_firmware","siemens:simatic_ipc377g_firmware","siemens:simatic_ipc427e_firmware","siemens:simatic_ipc477e_firmware","siemens:simatic_ipc627e_firmware","siemens:simatic_ipc647e_firmware","siemens:simatic_ipc677e_firmware","siemens:simatic_ipc847e_firmware","siemens:simatic_itp1000_firmware"],"source":"nvd","synced_at":"2026-10-19T21:27:20.926095847+00:00"},"epss":{"cve":"CVE-2021-33627","score":0.00328,"percentile":0.25947,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}