Authentication bypass via undisclosed Netlogon spoofing
Published Sep 8, 2026 · Updated Sep 9, 2026
Authentication bypass in Microsoft Windows Netlogon allows remote attackers to spoof authentication over an adjacent network. Microsoft has not published the affected Netlogon operation or explained how crafted network input defeats its authentication decision. Exploitation requires an adjacent-network position and high-complexity conditions without prior authentication; the identity or access obtained through spoofing remains undisclosed.
Summary
What happened
Authentication bypass in Microsoft Windows Netlogon allows remote attackers to spoof authentication over an adjacent network. Microsoft has not published the affected Netlogon operation or explained how crafted network input defeats its authentication decision. Exploitation requires an adjacent-network position and high-complexity conditions without prior authentication; the identity or access obtained through spoofing remains undisclosed.
The record
- CVE
- CVE-2026-62759
- Published
- Sep 8, 2026
- Updated
- Sep 9, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2019
- Classifications
- CWE-290, T1557
- Attack vector
- adjacent
- Privileges
- unauthenticated
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=10.0.17763.0 <10.0.17763.9245
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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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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