{"cve":"CVE-2021-33626","nvd":{"published":"2021-10-01T03:15:06.593","modified":"2026-08-11T13:17:19.523","status":"Modified","description":"A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer(QWORD values for CommBuffer). This can be used by an attacker to corrupt data in SMRAM memory and even lead to arbitrary code execution.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-829"],"references":["https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf","https://security.netapp.com/advisory/ntap-20220216-0006/","https://www.insyde.com/security-pledge","https://www.insyde.com/security-pledge/SA-2021001","https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf"],"products":["insyde:insydeh2o","siemens:ruggedcom_apr1808_firmware","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_ipc477e_pro_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":"2026-10-19T21:23:41.316049955+00:00"},"epss":{"cve":"CVE-2021-33626","score":0.00308,"percentile":0.23645,"date":"2026-11-01"},"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."]}