CVE-2025-59257

Published: Oct 14, 2025

Modified: Feb 22, 2026

PUBLISHED

CVSS v3.1

6.5

MEDIUM

Improper validation of specified type of input in Windows Local Session Manager (LSM) allows an authorized attacker to deny service over a network.

Vendor	Product	Versions
Microsoft	Windows 11 Version 24H2	affected `10.0.26100.0 - < 10.0.26100.6899`
Microsoft	Windows 11 Version 25H2	affected `10.0.26200.0 - < 10.0.26200.6899`
Microsoft	Windows Server 2022, 23H2 Edition (Server Core installation)	affected `10.0.25398.0 - < 10.0.25398.1913`
Microsoft	Windows Server 2025	affected `10.0.26100.0 - < 10.0.26100.6899`
Microsoft	Windows Server 2025 (Server Core installation)	affected `10.0.26100.0 - < 10.0.26100.6899`

CVSS v3.1 Vector

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

vendor-advisory

patch

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