Local privilege escalation through undisclosed kernel flaw
Published Jul 14, 2021 · Updated Aug 10, 2026
Privilege escalation in the Windows kernel on affected Windows 8.1, Windows 10, and Windows Server builds allows local users to gain elevated privileges. Microsoft has not published the named kernel locus or the incorrect operation performed on attacker-controlled input. Exploitation requires existing low-privilege access and yields high-privilege code execution on the same host; CISA lists the flaw as exploited.
Summary
What happened
Privilege escalation in the Windows kernel on affected Windows 8.1, Windows 10, and Windows Server builds allows local users to gain elevated privileges. Microsoft has not published the named kernel locus or the incorrect operation performed on attacker-controlled input. Exploitation requires existing low-privilege access and yields high-privilege code execution on the same host; CISA lists the flaw as exploited.
The record
- CVE
- CVE-2021-33771
- Published
- Jul 14, 2021
- Updated
- Aug 10, 2026
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-119, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 14, 2021CVE publishedPublication date reported by the CVE source.
- Nov 3, 2021Exploitation reportedCISA Known Exploited Vulnerabilities listing
- Aug 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=10.0.10240.0 <10.0.10240.19003
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.
Reported exploitation
- CISA Known Exploited Vulnerabilities listingknown exploited catalog
Technologies
Your stack
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Your stack
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