CVE-2021-40450
Exploited in the wild. In CISA KEV since 2022‑04‑25. Fixed versions are out.
What to do
Find your product and version, then upgrade to the build on the right.
- Microsoft Windows 10 Version 1809Affected: ≥ 10.0.0, < 10.0.17763.2237Upgrade to: 10.0.17763.2237Affected: ≥ 10.0.0, < 10.0.18363.1854Upgrade to: 10.0.18363.1854Affected: ≥ 10.0.0, < 10.0.19043.1288Upgrade to: 10.0.19043.1288Affected: ≥ 10.0.0, < 10.0.19041.1288Upgrade to: 10.0.19041.1288 + 1 more branchStated by: CVE record
- Microsoft Windows 11 version 21H2Affected: ≥ 10.0.0, < 10.0.22000.258Upgrade to: 10.0.22000.258Stated by: CVE record
- Microsoft Windows Server version 2004Affected: ≥ 10.0.0, < 10.0.19041.1288Upgrade to: 10.0.19041.1288Affected: ≥ 10.0.0, < 10.0.19042.1288Upgrade to: 10.0.19042.1288Stated by: CVE record
- Microsoft Windows Server 2019Affected: ≥ 10.0.0, < 10.0.17763.2237Upgrade to: 10.0.17763.2237Stated by: CVE record
- Microsoft Windows Server 2022Affected: ≥ 10.0.0, < 10.0.20348.288Upgrade to: 10.0.20348.288Stated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
Coverage timeline
0 publishersAdded to CISA KEV catalog
Sourced from public security reporting — each date is when it was published, not when it happened.
What it is
From the CVE record
Win32k Elevation of Privilege Vulnerability
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Listed as exploited in the wild since 2022-04-25.
US federal agencies must remediate by 2022-05-16.
Apply updates per vendor instructions.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
1.6% chance of exploitation activity in the next 30 days, which ranks it in the 75th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
- Attention now
Rising.
Lifecycle
6 events over 1716 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Added to CISA KEV
- Publishedweakness classified
Affected products
- Windows 10 Version 1809Operating Systems / windows
- Windows 11 version 21H2Operating Systems / windows
- Windows Server 2004 (Server Core Installation)Operating Systems / windows
- Windows Server 2019 (Server Core installation)Operating Systems / windows
- Windows Server 2022 (Server Core installation)Operating Systems / windows
And 28 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Scored 7.8 by NVD.
How it is reached
- Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
Watch the software you run.
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We'll flag the next CVE, public exploit or patch for Windows 10 Version 1809, not every advisory. This one: actively exploited.
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