{"id":"CVE-2021-43522","title":"An issue was discovered in Insyde InsydeH2O with kernel 5.1 through 2021-11-08, 5.2 through 2021-11-08, and 5.3 through 2021-11-08","summary":"An issue was discovered in Insyde InsydeH2O with kernel 5.1 through 2021-11-08, 5.2 through 2021-11-08, and 5.3 through 2021-11-08. A StorageSecurityCommandDxe SMM memory corruption vulnerability allows an attacker to write fixed or pred…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","cwe":["CWE-787"],"vendor":"insyde","product":"insydeh2o","affected":["insydeh2o >= 5.1, < 5.14.34","insydeh2o >= 5.2, < 5.24.34","insydeh2o >= 5.3, < 5.33.34"],"patched":["insydeh2o 5.33.34"],"published":"2022-02-03","updated":"2026-08-11","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-43522","references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20220216-0003/","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-20220216-0003/","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":0.00264,"epssPercentile":0.18603,"ingestedAt":"2026-08-11T16:47:01.627Z","slug":"CVE-2021-43522","body":"## Overview\n\nAn issue was discovered in Insyde InsydeH2O with kernel 5.1 through 2021-11-08, 5.2 through 2021-11-08, and 5.3 through 2021-11-08. A StorageSecurityCommandDxe SMM memory corruption vulnerability allows an attacker to write fixed or predictable data to SMRAM. Exploiting this issue could lead to escalating privileges to SMM.\n\n## Affected\n\n- `insydeh2o >= 5.1, < 5.14.34`\n- `insydeh2o >= 5.2, < 5.24.34`\n- `insydeh2o >= 5.3, < 5.33.34`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `insydeh2o 5.33.34`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}