Local privilege escalation via kernel heap overflow
Published Feb 10, 2026 · Updated Feb 10, 2026
Heap-based buffer overflow in the Microsoft Windows Kernel allows local users with low privileges to elevate privileges on affected systems. Microsoft identifies a heap overflow but does not disclose the kernel routine, input path, or incorrect memory operation that triggers it. Exploitation requires local low-privilege access and can compromise confidentiality, integrity, and availability at the elevated privilege level.
Summary
What happened
Heap-based buffer overflow in the Microsoft Windows Kernel allows local users with low privileges to elevate privileges on affected systems. Microsoft identifies a heap overflow but does not disclose the kernel routine, input path, or incorrect memory operation that triggers it. Exploitation requires local low-privilege access and can compromise confidentiality, integrity, and availability at the elevated privilege level.
The record
- CVE
- CVE-2026-21245
- Published
- Feb 10, 2026
- Updated
- Feb 10, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2025 (Server Core installation)
- Classifications
- CWE-787, CWE-122, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 10, 2026CVE publishedPublication date reported by the CVE source.
- Feb 10, 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 <10.0.26100.32370
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.
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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