Domain privilege escalation via sAMAccountName spoofing
Published Nov 10, 2021 · Updated Aug 19, 2026
Active Directory Domain Services in Microsoft Windows Server allows remote authenticated users to escalate privileges via sAMAccountName spoofing. The Security Accounts Manager accepted computer accounts whose sAMAccountName omitted the trailing dollar sign, allowing a domain user who could create or modify a machine account to impersonate a domain controller when chained with Kerberos processing. Exploitation requires domain credentials and directory permissions; successful attacks can obtain Domain Admin-level control.
Summary
What happened
Active Directory Domain Services in Microsoft Windows Server allows remote authenticated users to escalate privileges via sAMAccountName spoofing. The Security Accounts Manager accepted computer accounts whose sAMAccountName omitted the trailing dollar sign, allowing a domain user who could create or modify a machine account to impersonate a domain controller when chained with Kerberos processing. Exploitation requires domain credentials and directory permissions; successful attacks can obtain Domain Admin-level control.
The record
- CVE
- CVE-2021-42278
- Published
- Nov 10, 2021
- Updated
- Aug 19, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2019
- Classifications
- T1098
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Nov 10, 2021CVE publishedPublication date reported by the CVE source.
- Apr 11, 2022Exploitation reportedCISA Known Exploited Vulnerability listing
- 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?
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- Affected versionversion=10.0.17763.0 <10.0.17763.2300
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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Weakness, pattern, technique
Public exploit references
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Reported exploitation
- CISA Known Exploited Vulnerability listingknown exploited catalog
Technologies
Your stack
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Your stack
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