CVE-2021-43244

Kernel-memory disclosure to local low-privileged users

Published Dec 15, 2021 · Updated Aug 4, 2024

Windows Kernel information disclosure in affected Windows 10 and Windows Server builds allows local users to read kernel memory. Microsoft has not disclosed the concrete kernel component or the erroneous operation that exposes the information. Exploitation requires low-privileged local access and no user interaction; the documented consequence is confidentiality loss only.

CVSS severity6.5

Medium

EPSS probability0.82%

Next 30 days · Sep 16, 2026

Known exploitationUnconfirmed

Based on sourced intelligence

Hinoki checkNot available

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Summary

What happened

The record

CVE: CVE-2021-43244
Published: Dec 15, 2021
Updated: Aug 4, 2024

Vendor: Microsoft
Product: Windows Server 2019
Classifications: Unavailable

Attack vector: local
Privileges: authenticated

Timeline

How it unfolded

Dec 15, 2021CVE publishedPublication date reported by the CVE source.
Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

Affected versionversion=10.0.0 <10.0.17763.2366

What conditions does exploitation require?

Attack vectorlocal

Required privilegesauthenticated

What is affected?

Microsoft · Windows Server 2019version=10.0.0 <10.0.17763.2366

Microsoft · Windows 10 Version 21H1version=10.0.0 <10.0.19043.1415

Microsoft · Windows 10 Version 1909version=10.0.0 <10.0.18363.1977

Microsoft · Windows Server, version 2004version=10.0.0 <10.0.19041.1415

Microsoft · Windows 10 Version 21H2version=10.0.0 <10.0.19044.1415

Microsoft · Windows 10 Version 20H2version=10.0.0 <10.0.19042.1415

Microsoft · Windows Server 2019 (Server Core installation)version=10.0.0 <10.0.17763.2366

Microsoft · Windows Server version 20H2version=10.0.0 <10.0.19042.1415

Microsoft · Windows Server 2022version=10.0.0 <10.0.20348.405

Microsoft · Windows 10 Version 2004version=10.0.0 <10.0.19041.1415

Microsoft · Windows 10 Version 1809version=10.0.0 <10.0.17763.2366

Published CVSS scores

6.5MicrosoftCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

4.9NVDAV:L/AC:L/Au:N/C:C/I:N/A:N

5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026

Latest reporting daySep 16, 2026

Latest daily unique IPsUnavailable

Prior 30-day averageUnavailable

SourceShadowserver honeypots (KEV)

Vectorlocal

Privilegesauthenticated

Known exploitationUnconfirmed

Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

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