Privileged file deletion via directory junction
Published Mar 11, 2021 · Updated Aug 19, 2026
Improper privilege management in Windows Setup allows local users to delete files through a crafted directory junction. Windows Setup follows the attacker-created junction during a privileged file operation and deletes a file outside the intended setup directory. Low-privileged code execution is required; privileged file deletion can interrupt Windows, while Microsoft classifies the issue as elevation of privilege.
Summary
What happened
Improper privilege management in Windows Setup allows local users to delete files through a crafted directory junction. Windows Setup follows the attacker-created junction during a privileged file operation and deletes a file outside the intended setup directory. Low-privileged code execution is required; privileged file deletion can interrupt Windows, while Microsoft classifies the issue as elevation of privilege.
The record
- CVE
- CVE-2021-1729
- Published
- Mar 11, 2021
- Updated
- Aug 19, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2019
- Classifications
- CWE-269, T1485
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 11, 2021CVE publishedPublication date reported by the CVE source.
- Aug 19, 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 <10.0.17763.1817
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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