CVE-2023-21539 — Windows Authentication Remote Code Execution Vulnerability

Executive Summary

None

Overview

7.5

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Remote Code Execution

Weakness CWE-125: Out-of-bounds Read

Released Jan 10 2023

Last Updated Jan 10 2023

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01163 — 0.64456 percentile

NVD CVSS 7.5 HIGH — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

ATTACK VECTOR

Network

ATTACK COMPLEXITY

High

PRIVILEGES REQUIRED

Low

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

High

AVAILABILITY

High

EXPLOIT CODE MATURITY

Unproven

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 6.5

EPSS Score

0.01163

probability of exploitation in the next 30 days

0.64456 percentile - updated 2026-08-14

View on FIRST.org

Affected Products

14 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 Version 20H2 for 32-bit Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 20H2 for ARM64-based Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 21H2 for 32-bit Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 21H2 for ARM64-based Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 21H2 for x64-based Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 22H2 for 32-bit Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 22H2 for ARM64-based Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 10 Version 22H2 for x64-based Systems	`5022282 (Security Update)`	Important	Remote Code Execution	Yes
Windows 11 version 21H2 for ARM64-based Systems	`5022287 (Security Update)`	Important	Remote Code Execution	Yes
Windows 11 version 21H2 for x64-based Systems	`5022287 (Security Update)`	Important	Remote Code Execution	Yes
Windows 11 Version 22H2 for ARM64-based Systems	`5022303 (Security Update)`	Important	Remote Code Execution	Yes
Windows 11 Version 22H2 for x64-based Systems	`5022303 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2022	`5022291 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2022 (Server Core installation)	`5022291 (Security Update)`	Important	Remote Code Execution	Yes

Patches

4 patches

Article	Type	Restart
`5022282`	Security Update	Yes
`5022287`	Security Update	Yes
`5022303`	Security Update	Yes
`5022291`	Security Update	Yes

Exploits & PoC

No public exploit or PoC has been linked for this CVE yet. When available, references are sourced from public repositories and may be unverified or non-functional — review carefully before use.

Detection Rules

No public Sigma or Nuclei detection rule has been mapped to this CVE yet. Coverage is concentrated on exploited / high-profile vulnerabilities; check SigmaHQ for updates.

Acknowledgments

Alexander Clouter with coreMem Limited

References

MSRC Advisory MITRE NVD