CVE-2026-21533
LPE in Microsoft Windows 10 21H2 ≤ 10.0.19044.6937
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2026-21533 is a high-severity Improper Privilege Management (CWE-269) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Abuse Elevation Control Mechanism (T1548); ranked in the top 11% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
The strongest mitigations our analysis identified map to AC-2 (Account Management) and AC-24 (Access Control Decisions) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-21533 is an improper privilege management vulnerability in Windows Remote Desktop that enables local privilege escalation. It affects the Windows Remote Desktop component and carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), mapped to CWE-269 (Improper Privilege Management). The issue was published on 2026-02-10.
An authorized local attacker with low privileges can exploit this vulnerability with low complexity and no user interaction required. Successful exploitation allows the attacker to gain high-impact access to confidentiality, integrity, and availability, effectively elevating privileges on the affected system.
Microsoft's update guide at msrc.microsoft.com provides details on patching the vulnerability. Vicarius offers detection and mitigation scripts specifically for this privilege escalation issue in Windows Remote Desktop. The vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.
This CVE has seen real-world exploitation, as indicated by its inclusion in CISA's catalog, underscoring the need for immediate patching in environments using Windows Remote Desktop.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-7343
Vulnerability Data
Improper privilege management in Windows Remote Desktop allows an authorized attacker to elevate privileges locally.
- CWE(s)
- KEV Date Added
- 10 February 2026
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 5 hardening rules · 5 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Account management directly governs assignment and tracking of privileges so proper implementation stops the weakness from being introduced.
Requiring explicit access-control decisions ensures privileges are evaluated rather than assumed or omitted.
Access enforcement applies the correct privilege checks at every request, structurally preventing unintended spheres of control.
Separation of duties constrains how privileges may be assigned, reducing the chance of overly broad actor control.
Least privilege is the direct countermeasure to improper privilege management; implementing it eliminates the root cause.
Binding security attributes to subjects/objects supplies the mechanism needed to track and enforce privileges correctly.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.AA-05 enforces least privilege/SoD and periodic reviews that directly remove most privilege-assignment defects, yet CWE-269 also covers escalation paths and role design outside a single access-management control.
PR.AA-01 supplies credential/identity lifecycle support that can reduce some privilege-assignment errors but does not itself assign, modify, or check privileges, leaving most of CWE-269's risk unaddressed.
Config baselines and default reviews can enforce some privilege-related settings (one facet) but do not address code-level assignment/tracking logic that defines CWE-269.
PR.PS-05 can partially limit exploitability of some privilege issues via execution restrictions, but does not address the core design/implementation flaws of CWE-269 at all.
PR.DS-10 protects data-in-use without touching privilege assignment/tracking, so it neither prevents CWE-269 nor removes more than one narrow facet of its risk.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Requiring owner approval, segregation of duties, and periodic reviews prevents the assignment of excessive or unnecessary privileges to users or processes.
Enforcing minimum-necessary privileges, temporary grants, and separation of administrative versus normal identities prevents the over-assignment of rights that CWE-269 describes.
Dynamic techniques that grant the minimum necessary rights for a given time window and revoke them afterward reduce the window in which excessive or unnecessary privileges can be exploited.
Explicit restrictions on privileged access and segregation of duties limit the scope of privileges that can be assigned, reducing the chance that excessive or unnecessary privileges are granted to entities.
Defining and communicating authorization levels for each role limits the assignment of excessive or unnecessary privileges.
Separating duties such as developing software from administering production systems prevents any one person from accumulating excessive privileges that would constitute improper privilege management.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Windows 10 (1 rule)
- V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows 11 (1 rule)
- V-253269 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows Server 2016 (1 rule)
- V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-269
Windows Server 2019 (1 rule)
- V-205746 Windows Server 2019 must only allow Administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269
Windows Server 2022 (1 rule)
- V-254428 Windows Server 2022 must only allow administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269