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 1803
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows 10 Version 1809
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows Server 2019
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows Server 2019 (Server Core installation)
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows 10 Version 1909
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows Server, version 1909 (Server Core installation)
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows 10 Version 2004
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows Server version 2004
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows 10 Version 20H2
Default status: Not specified
- affected: 10.0.0 to < publication (custom)
Microsoft / Windows Server version 20H2
Default status: Not specified
- affected: 10.0.0 to < publication (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": 0.08398,
"percentile": 0.95059
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.08398,
"percentile": 0.95027
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.08398,
"percentile": 0.95021
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.08398,
"percentile": 0.95018
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.08398,
"percentile": 0.95016
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.08398,
"percentile": 0.95008
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.08398,
"percentile": 0.95003
}05 Nov 2026, 18:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"cna": {
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{
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{
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"ARM64-based Systems"
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"product": "Windows 10 Version 1909",
"vendor": "Microsoft",
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{
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"cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*"
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"product": "Windows Server version 2004",
"vendor": "Microsoft",
"versions": [
{
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{
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"cpe:2.3:o:microsoft:windows_10_20H2:*:*:*:*:*:*:x86:*",
"cpe:2.3:o:microsoft:windows_10_20H2:*:*:*:*:*:*:arm64:*"
],
"platforms": [
"32-bit Systems",
"ARM64-based Systems"
],
"product": "Windows 10 Version 20H2",
"vendor": "Microsoft",
"versions": [
{
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},
{
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"cpe:2.3:o:microsoft:windows_server_20H2:*:*:*:*:*:*:*:*"
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"x64-based Systems"
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"vendor": "Microsoft",
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"lang": "en-US",
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],
"title": "Win32k Elevation of Privilege Vulnerability"
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},
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"datePublished": "2021-04-13T19:32:47.000Z",
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.08398,
"percentile": 0.94999
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.08398,
"percentile": 0.9499
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.08398,
"percentile": 0.94984
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-28310",
"cwes": [
"CWE-787"
],
"dateAdded": "2021-11-03",
"dueDate": "2021-11-17",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-28310",
"product": "Win32k",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Microsoft Windows Win32k contains an unspecified vulnerability that allows for privilege escalation.",
"vendorProject": "Microsoft",
"vulnerabilityName": "Microsoft Win32k Privilege Escalation Vulnerability"
}