CVE-2026-58634

Local privilege escalation via use-after-free

Published Jul 14, 2026 · Updated Jul 14, 2026

Use-after-free in Desktop Window Manager in Microsoft Windows 11 version 26H1 allows local users to elevate privileges. Microsoft identifies the affected component and memory-lifetime error but has not published the object, function, or stale-reference operation that triggers the freed-memory access. Exploitation requires local low-privileged access and can yield high-privilege execution within the affected system.

CVSS severity7.8
High
EPSS probability0.33%
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 Desktop Window Manager in Microsoft Windows 11 version 26H1 allows local users to elevate privileges. Microsoft identifies the affected component and memory-lifetime error but has not published the object, function, or stale-reference operation that triggers the freed-memory access. Exploitation requires local low-privileged access and can yield high-privilege execution within the affected system.

The record

CVE
CVE-2026-58634
Published
Jul 14, 2026
Updated
Jul 14, 2026
Vendor
Microsoft
Product
Windows 11, version 26H1
Classifications
CWE-416, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 14, 2026Record 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=10.0.28000.0 <10.0.28000.2525

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Windows 11, version 26H1version=10.0.28000.0 <10.0.28000.2525

Published CVSS scores

7.8Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:L/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
Privilegesauthenticated
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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