{"id":"CVE-2021-45971","title":"An issue was discovered in SdHostDriver in Insyde InsydeH2O with kernel 5.1 before 05.16.25, 5.2 before 05.26.25, 5.3 before 05.35.25, 5.4 before 05.43.25, and 5.5 before 05.51.25","summary":"An issue was discovered in SdHostDriver in Insyde InsydeH2O with kernel 5.1 before 05.16.25, 5.2 before 05.26.25, 5.3 before 05.35.25, 5.4 before 05.43.25, and 5.5 before 05.51.25. A vulnerability exists in the SMM (System Management Mod…","severity":"high","cvss":8.2,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H","cwe":["CWE-787"],"vendor":"insyde","product":"insydeh2o","affected":["insydeh2o >= 5.1, < 5.16.25","insydeh2o >= 5.2, < 5.26.25","insydeh2o >= 5.3, < 5.35.25","insydeh2o >= 5.4, < 5.43.25","insydeh2o >= 5.5, < 05.51.25"],"patched":["insydeh2o 05.51.25"],"published":"2022-01-06","updated":"2026-08-11","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-45971","references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20220216-0004/","label":"cve@mitre.org"},{"url":"https://www.insyde.com/security-pledge","label":"cve@mitre.org"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20220216-0004/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.insyde.com/security-pledge","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.kb.cert.org/vuls/id/796611","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-306654.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.00279,"epssPercentile":0.20629,"ingestedAt":"2026-08-11T16:47:01.590Z","slug":"CVE-2021-45971","body":"## Overview\n\nAn issue was discovered in SdHostDriver in Insyde InsydeH2O with kernel 5.1 before 05.16.25, 5.2 before 05.26.25, 5.3 before 05.35.25, 5.4 before 05.43.25, and 5.5 before 05.51.25. A vulnerability exists in the SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer (CommBufferData).\n\n## Affected\n\n- `insydeh2o >= 5.1, < 5.16.25`\n- `insydeh2o >= 5.2, < 5.26.25`\n- `insydeh2o >= 5.3, < 5.35.25`\n- `insydeh2o >= 5.4, < 5.43.25`\n- `insydeh2o >= 5.5, < 05.51.25`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `insydeh2o 05.51.25`","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":45.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}