CVE-2026-20838

Generation of error message containing sensitive information in Windows Kernel allows an authorized attacker to disclose information locally.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20838	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_23h2::::::::
	cpe:2.3:o:microsoft:windows_11_24h2::::::::
	cpe:2.3:o:microsoft:windows_11_25h2::::::::
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2022_23h2::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

17 Jun 2026, 10:17

Type	Values Removed	Values Added
Summary		(es) Generación de mensaje de error que contiene información sensible en el kernel de Windows permite a un atacante autorizado divulgar información localmente.

15 Jan 2026, 15:15

Type	Values Removed	Values Added
CPE		cpe:2.3:o:microsoft:windows_server_2025:::::::: cpe:2.3:o:microsoft:windows_11_23h2:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_11_25h2:::::::: cpe:2.3:o:microsoft:windows_server_2022_23h2:::::::: cpe:2.3:o:microsoft:windows_11_24h2::::::::
First Time		Microsoft windows Server 2022 Microsoft Microsoft windows 11 23h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows Server 2025 Microsoft windows Server 2022 23h2
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20838 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20838 - Vendor Advisory

13 Jan 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-13 18:16

Updated : 2026-06-17 10:17

NVD link : CVE-2026-20838

Mitre link : CVE-2026-20838

CVE.ORG link : CVE-2026-20838

JSON object : View

Products Affected

microsoft

windows_11_25h2
windows_11_24h2
windows_server_2022_23h2
windows_11_23h2
windows_server_2022
windows_server_2025

CWE

CWE-209

Generation of Error Message Containing Sensitive Information

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