Privilege escalation via permissive LDAP object authorization
Published Nov 10, 2021 · Updated Aug 19, 2026
Improper authorization in Microsoft Windows Server AD DS allows remote authenticated users to elevate privileges through crafted LDAP requests. LDAP Add accepts attacker-chosen security-sensitive attributes on new computer-derived objects, while LDAP Modify preserves excessive implicit-owner rights over security descriptors. Exploitation requires permission to create a computer-derived object and can grant control beyond the user's delegated directory privileges.
Summary
What happened
Improper authorization in Microsoft Windows Server AD DS allows remote authenticated users to elevate privileges through crafted LDAP requests. LDAP Add accepts attacker-chosen security-sensitive attributes on new computer-derived objects, while LDAP Modify preserves excessive implicit-owner rights over security descriptors. Exploitation requires permission to create a computer-derived object and can grant control beyond the user's delegated directory privileges.
The record
- CVE
- CVE-2021-42291
- 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.
- 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?
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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