CVE & CISA-KEV Catalog

CVE-2025-59259

MEDIUMEPSS 73th pctl
6.5
CVSS v3
NVD

Description

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

How to fix

Remediation Available
Windows 10Windows
Install:KB5066837Microsoft
Windows 10 Version 1607Windows
Install:KB5066836Microsoft
Windows 10 Version 1809Windows
Install:KB5066586Microsoft
Windows 10 Version 21H2Windows
Install:KB5066791Microsoft
Windows 10 Version 22H2Windows
Install:KB5066791Microsoft
Windows 11 Version 22H2Windows
Install:KB5066793Microsoft
Windows 11 Version 23H2Windows
Install:KB5066793Microsoft
Windows 11 Version 24H2Windows
Install:KB5066835Microsoft
Windows 11 Version 25H2Windows
Install:KB5066835Microsoft
Windows Server 2012Windows
Install:KB5066875Microsoft
Windows Server 2012 (Server Core installation)Windows
Install:KB5066875Microsoft
Windows Server 2012 R2Windows
Install:KB5066873Microsoft
Windows Server 2012 R2 (Server Core installation)Windows
Install:KB5066873Microsoft
Windows Server 2016Windows
Install:KB5066836Microsoft
Windows Server 2016 (Server Core installation)Windows
Install:KB5066836Microsoft
Windows Server 2019Windows
Install:KB5066586Microsoft
Windows Server 2019 (Server Core installation)Windows
Install:KB5066586Microsoft
Windows Server 2022Windows
Install:KB5066782Microsoft
Windows Server 2022 (Server Core installation)Windows
Install:KB5066782Microsoft
Windows Server 2022, 23H2 Edition (Server Core installation)Windows
Install:KB5066780Microsoft
Windows Server 2025Windows
Install:KB5066835Microsoft
Windows Server 2025 (Server Core installation)Windows
Install:KB5066835Microsoft

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityNone
AvailabilityHigh

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

Exploit Intelligence

1.51%probability of exploitation in 30 days
73rdpercentile

Elevated risk: more likely to be exploited than 73% of all known CVEs.

References

Vendor Advisory1

Related Vulnerabilities

Other CWE-1287 (Improper Validation of Specified Type of Input) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2024-4879Critical9.8100%KEV-
CVE-2022-31007Medium4.927%-Fix
CVE-2024-6298Critical10.019%--
CVE-2026-25639High7.52.7%-Fix
CVE-2026-59680High8.02.3%--
CVE-2021-43802Critical9.92.0%-Fix

Common questions

How do I fix CVE-2025-59259?

Published advisories record a fix for 22 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2025-59259 being actively exploited?

Not that we know of. CVE-2025-59259 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 1.5% is the estimated probability that it will be exploited in the next 30 days. That is higher than 73% of all scored CVEs.

How severe is CVE-2025-59259?

CVE-2025-59259 has a CVSS v3 base score of 6.5, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2025-59259 affect?

Published advisories record a fix for Windows 10 (Windows), Windows 10 Version 1607 (Windows), Windows 10 Version 1809 (Windows), Windows 10 Version 21H2 (Windows), and 18 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2025-59259
CVE-2025-59259 severity badge

Markdown

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HTML

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-17.