Exploitation evidence
Known exploited · CISA KEV listed
Added 2021-11-03. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2021-11-17. 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 1909
Default status: Not specified
- affected: 10.0.0 to < 10.0.18363.1621 (custom)
Microsoft / Windows 10 Version 21H1
Default status: Not specified
- affected: 10.0.0 to < 10.0.19043.1052 (custom)
Microsoft / Windows 10 Version 2004
Default status: Not specified
- affected: 10.0.0 to < 10.0.19041.1052 (custom)
Microsoft / Windows Server version 2004
Default status: Not specified
- affected: 10.0.0 to < 10.0.19041.1052 (custom)
Microsoft / Windows 10 Version 20H2
Default status: Not specified
- affected: 10.0.0 to < 10.0.19042.1052 (custom)
Microsoft / Windows Server version 20H2
Default status: Not specified
- affected: 10.0.0 to < 10.0.19042.1052 (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
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": 0.06609,
"percentile": 0.93944
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.06609,
"percentile": 0.93907
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.06609,
"percentile": 0.93899
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.06609,
"percentile": 0.93896
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.06609,
"percentile": 0.93892
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.06609,
"percentile": 0.93883
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.06609,
"percentile": 0.93878
}05 Nov 2026, 12:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"cna": {
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.06609,
"percentile": 0.93874
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.06609,
"percentile": 0.93863
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.06555,
"percentile": 0.93815
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-33739",
"cwes": [],
"dateAdded": "2021-11-03",
"dueDate": "2021-11-17",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-33739",
"product": "Windows",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Microsoft Desktop Window Manager (DWM) Core Library contains an unspecified vulnerability that allows for privilege escalation.",
"vendorProject": "Microsoft",
"vulnerabilityName": "Microsoft Desktop Window Manager (DWM) Core Library Privilege Escalation Vulnerability"
}