Exploitation evidence
Known exploited · CISA KEV listed
Added 2022-02-10. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2022-02-24. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Microsoft / Windows 10 Version 1809
Default status: Not specified
- affected: 10.0.17763.0 to < 10.0.17763.2114 (custom)
Microsoft / Windows 10 Version 1809
Default status: Not specified
- affected: 10.0.0 to < 10.0.17763.2114 (custom)
Microsoft / Windows 10 Version 1909
Default status: Not specified
- affected: 10.0.0 to < 10.0.18363.1734 (custom)
Microsoft / Windows 10 Version 2004
Default status: Not specified
- affected: 10.0.0 to < 10.0.19041.1165 (custom)
Microsoft / Windows 10 Version 20H2
Default status: Not specified
- affected: 10.0.0 to < 10.0.19042.1165 (custom)
Microsoft / Windows 10 Version 21H1
Default status: Not specified
- affected: 10.0.0 to < 10.0.19043.1165 (custom)
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
CVE Program record ↗ · Download tracked evidence as JSON
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36934
- https://www.kb.cert.org/vuls/id/506989
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36934
- http://packetstormsecurity.com/files/164006/HiveNightmare-AKA-SeriousSAM.html
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36934
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.67252,
"percentile": 0.99313
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.67252,
"percentile": 0.9931
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.67252,
"percentile": 0.99309
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.67252,
"percentile": 0.99308
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.67252,
"percentile": 0.99307
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.67252,
"percentile": 0.99307
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.67252,
"percentile": 0.99306
}05 Nov 2026, 06:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.67252,
"percentile": 0.99305
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.67252,
"percentile": 0.99303
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.67252,
"percentile": 0.99302
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-36934",
"cwes": [
"CWE-1220"
],
"dateAdded": "2022-02-10",
"dueDate": "2022-02-24",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-36934",
"product": "Windows",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "If a Volume Shadow Copy (VSS) shadow copy of the system drive is available, users can read the SAM file which would allow any user to escalate privileges to SYSTEM level.",
"vendorProject": "Microsoft",
"vulnerabilityName": "Microsoft Windows SAM Local Privilege Escalation Vulnerability"
}