CVE-2023-28274

SYSTEM privilege escalation via undisclosed Win32k flaw

Published Apr 11, 2023 · Updated Jan 23, 2025

Improper input validation in Win32k in affected Windows releases allows local users to elevate privileges to SYSTEM. Microsoft identifies Win32k as the affected component but has not disclosed the input, code locus, or validation operation that fails. Exploitation requires existing low-privileged access to the target, after which the attacker gains complete control under the SYSTEM account.

CVSS severity7.8
High
EPSS probability6.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Win32k in affected Windows releases allows local users to elevate privileges to SYSTEM. Microsoft identifies Win32k as the affected component but has not disclosed the input, code locus, or validation operation that fails. Exploitation requires existing low-privileged access to the target, after which the attacker gains complete control under the SYSTEM account.

The record

CVE
CVE-2023-28274
Published
Apr 11, 2023
Updated
Jan 23, 2025
Vendor
Microsoft
Product
Windows Server 2019
Classifications
CWE-20, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 11, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=10.0.17763.0 <10.0.17763.4252

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Windows Server 2019version=10.0.17763.0 <10.0.17763.4252
Microsoft · Windows 11 version 21H2version=10.0.0 <10.0.22000.1817
Microsoft · Windows 10 Version 21H2version=10.0.19043.0 <10.0.19044.2846
Microsoft · Windows 10 Version 20H2version=10.0.0 <10.0.19042.2846
Microsoft · Windows 10 Version 22H2version=10.0.19045.0 <10.0.19045.2846
Microsoft · Windows Server 2019 (Server Core installation)version=10.0.17763.0 <10.0.17763.4252
Microsoft · Windows 11, version 22H2version=10.0.22621.0 <10.0.22621.1555
Microsoft · Windows Server 2022version=10.0.20348.0 <10.0.20348.1668
Microsoft · Windows 10 Version 1809version=10.0.0 <10.0.17763.4252; version=10.0.17763.0 <10.0.17763.4252

Published CVSS scores

7.8MicrosoftCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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

CWE-20Improper Input Validation
T1068Exploitation for Privilege Escalation

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

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Your stack

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