CVE-2025-53809

Improper input validation in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to deny service over a network.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53809	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_24h2::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

18 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Validación de entrada incorrecta en el Servicio del Subsistema de la Autoridad de Seguridad Local de Windows (LSASS) permite a un atacante autorizado denegar el servicio a través de una red.

Information

Published : 2025-09-09 17:15

Updated : 2026-10-18 21:10

NVD link : CVE-2025-53809

Mitre link : CVE-2025-53809

CVE.ORG link : CVE-2025-53809

JSON object : View

Products Affected

microsoft

windows_11_24h2
windows_server_2025

CWE

CWE-20

Improper Input Validation

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