CVE-2021-36934Windows Elevation of Privilege Vulnerability
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. An attacker must have the ability to execute code on a victim system to exploit this vulnerability. After installing this security update, you must manually delete all shadow copies of system files, including the SAM database, to fully mitigate this vulnerabilty. Simply installing this security update will not fully mitigate this vulnerability. See KB5005357- Delete Volume Shadow Copies.
Overview
Severity
| Score | Severity | Version | Vector String |
|---|---|---|---|
| 7.8 | HIGH | 3.1microsoft (CNA) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 7.8 | HIGH | 3.1microsoft (CNA) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:T/RC:C |
| 4.6 | MEDIUM | 2.0NVD | AV:L/AC:L/Au:N/C:P/I:P/A:P |
CISA required action
⚡ Known exploited · remediation due Feb 24, 2022
Apply updates per vendor instructions.
Details
- CVE ID
- CVE-2021-36934
- Status
- Analyzed
- Assigner (CNA)
- microsoft
- Published
- Jul 22, 2021
- Last modified
- 2026-08-10 20:19 UTC
- Weaknesses
Affected Products
As published by the CNA in the CVE record.
MicrosoftWindows 10 Version 18091 version range
- 10.0.17763.0 before 10.0.17763.2114
MicrosoftWindows 10 Version 18091 version range
- 10.0.0 before 10.0.17763.2114
MicrosoftWindows 10 Version 19091 version range
- 10.0.0 before 10.0.18363.1734
MicrosoftWindows 10 Version 20041 version range
- 10.0.0 before 10.0.19041.1165
MicrosoftWindows 10 Version 20H21 version range
- 10.0.0 before 10.0.19042.1165
MicrosoftWindows 10 Version 21H11 version range
- 10.0.0 before 10.0.19043.1165
References
- msrc.microsoft.com https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36934
- packetstormsecurity.com http://packetstormsecurity.com/files/164006/HiveNightmare-AKA-SeriousSAM.html
- portal.msrc.microsoft.com https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36934
- kb.cert.org https://www.kb.cert.org/vuls/id/506989
- cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36934