Local privilege escalation via MIDI TOCTOU race
Published Sep 8, 2026 · Updated Sep 9, 2026
A TOCTOU race in the Windows MIDI Service Module in Windows 11 allows local users with low privileges to elevate privileges. Microsoft has not published the checked resource, competing operation, or precise privilege gained. Exploitation requires local low-privilege access and winning a high-complexity race, with confidentiality, integrity, and availability impacts.
Summary
What happened
A TOCTOU race in the Windows MIDI Service Module in Windows 11 allows local users with low privileges to elevate privileges. Microsoft has not published the checked resource, competing operation, or precise privilege gained. Exploitation requires local low-privilege access and winning a high-complexity race, with confidentiality, integrity, and availability impacts.
The record
- CVE
- CVE-2026-69440
- Published
- Sep 8, 2026
- Updated
- Sep 9, 2026
- Vendor
- Microsoft
- Product
- Windows 11, version 25H2
- Classifications
- CWE-367, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 8, 2026CVE publishedPublication date reported by the CVE source.
- Sep 9, 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.
- Affected versionversion=10.0.26200.0 <10.0.26200.9445
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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