CVE-2025-59206

Local privilege escalation via use-after-free

Published Oct 14, 2025 · Updated Oct 14, 2025

Use-after-free in the Microsoft ReFS Deduplication Service allows local users to elevate privileges on affected Windows systems. Microsoft identifies the service and weakness class but has not disclosed the freed object, triggering input, or stale-reference path. Exploitation requires local access and high-complexity conditions; success grants elevated privileges with broad system impact.

CVSS severity7.4
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Microsoft ReFS Deduplication Service allows local users to elevate privileges on affected Windows systems. Microsoft identifies the service and weakness class but has not disclosed the freed object, triggering input, or stale-reference path. Exploitation requires local access and high-complexity conditions; success grants elevated privileges with broad system impact.

The record

CVE
CVE-2025-59206
Published
Oct 14, 2025
Updated
Oct 14, 2025
Vendor
Microsoft
Product
Windows Server 2025 (Server Core installation)
Classifications
CWE-416, T1068
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 14, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 14, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0.26100.0 <10.0.26100.6899

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Windows Server 2025 (Server Core installation)version=10.0.26100.0 <10.0.26100.6899
Microsoft · Windows 11, version 25H2version=10.0.26200.0 <10.0.26200.6899
Microsoft · Windows 11, version 24H2version=10.0.26100.0 <10.0.26100.6899
Microsoft · Windows Server 2025version=10.0.26100.0 <10.0.26100.6899

Published CVSS scores

7.4Microsoft CorporationCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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