SYSTEM code execution via symbolic-link directory deletion
Published Nov 10, 2021 · Updated Aug 19, 2026
Improper privilege management in Microsoft Diagnostics Hub Standard Collector allows local users to gain SYSTEM access through a symbolic link. The service follows an attacker-created symbolic link when deleting a directory, redirecting its privileged deletion to an attacker-chosen location. Exploitation requires low-privileged code execution on the host and can lead to arbitrary code execution as SYSTEM.
Summary
What happened
Improper privilege management in Microsoft Diagnostics Hub Standard Collector allows local users to gain SYSTEM access through a symbolic link. The service follows an attacker-created symbolic link when deleting a directory, redirecting its privileged deletion to an attacker-chosen location. Exploitation requires low-privileged code execution on the host and can lead to arbitrary code execution as SYSTEM.
The record
- CVE
- CVE-2021-42277
- Published
- Nov 10, 2021
- Updated
- Aug 19, 2026
- Vendor
- Microsoft
- Product
- Microsoft Visual Studio 2019
- Classifications
- CWE-269, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Nov 10, 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=15.0.0 <16.9.13
- Affected versionversion=16.0.0 <16.7.21
- Affected versionversion=16.11.0 <16.11.6
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
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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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