Local privilege escalation via Win32K heap overflow
Published Sep 8, 2026 · Updated Sep 9, 2026
A heap-based buffer overflow in Microsoft Windows Win32K allows local users with existing access to elevate privileges on affected systems. Microsoft identifies the affected locus only as Win32K and has not disclosed the specific routine or operation that mishandles attacker-controlled data on the heap. Exploitation requires low-privilege local access and no user interaction, and successful exploitation elevates the user's privileges on the affected host.
Summary
What happened
A heap-based buffer overflow in Microsoft Windows Win32K allows local users with existing access to elevate privileges on affected systems. Microsoft identifies the affected locus only as Win32K and has not disclosed the specific routine or operation that mishandles attacker-controlled data on the heap. Exploitation requires low-privilege local access and no user interaction, and successful exploitation elevates the user's privileges on the affected host.
The record
- CVE
- CVE-2026-69348
- Published
- Sep 8, 2026
- Updated
- Sep 9, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2025 (Server Core installation)
- Classifications
- CWE-122, 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=10.0.26100.0 <10.0.26100.33438
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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