CVE-2021-36934
<p>An elevation of privilege vulnerability exists because of overly permissive Access Control Lists (ACLs) on multiple system files, including the Security Accounts Manager (SAM) database. An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.</p> <p>An attacker must have the ability to execute code on a victim system to exploit this vulnerability.</p> <p>After installing this security update, you <em>must</em> manually delete all shadow copies of system files, including the SAM database, to fully mitigate this vulnerabilty. <strong>Simply installing this security update will not fully mitigate this vulnerability.</strong> See <a href="https://support.microsoft.com/topic/1ceaa637-aaa3-4b58-a48b-baf72a2fa9e7">KB5005357- Delete Volume Shadow Copies</a>.</p>
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Microsoft Windows SAM Local Privilege Escalation Vulnerability
Microsoft Windows
Apply updates per vendor instructions.
2/10/2022
https://nvd.nist.gov/vuln/detail/CVE-2021-36934
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v2 Score
AV:L/AC:L/Au:N/C:P/I:P/A:P
EPSS Score (Exploitation Probability)
This vulnerability has a 90.42% probability of being exploited in the next 30 days, ranking higher than 100% of all scored CVEs.
CWE Classification
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Similar SeverityHIGH
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