CVE-2026-21533: Technical Deep-Dive (Auto Refreshed)

Generated on 2026-03-23T21:45:45.255Z. This file is automatically regenerated every 30 minutes by the CVE AI enrichment job using web sources (NVD, MITRE, CISA KEV, GitHub).

Executive Technical Summary

Improper privilege management in Windows Remote Desktop allows an authorized attacker to elevate privileges locally.

• Context preserved from previous revision: Improper privilege management in Windows Remote Desktop allows an authorized attacker to elevate privileges locally. Notes: 📡 PoC auto collect from GitHub. ⚠️ Be careful Malware.

Technical Details

• CVE: CVE-2026-21533
• KEV date added: 2026-02-10
• KEV due date: 2026-03-03
• NVD published: 2026-02-10
• NVD modified: 2026-02-11
• MITRE modified: 2026-03-16
• CVSS base score: 7.8
• CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
• CVSS exploitability score: 1.8
• CVSS impact score: 5.9
• Attack vector: Local
• Attack complexity: Low
• Privileges required: Low
• User interaction: None
• Scope: Unchanged
• Confidentiality impact: High
• Integrity impact: High
• Availability impact: High

Versions and Products Impacted

• microsoft / windows 10 1607 (versions: < 10.0.14393.8868)
• microsoft / windows 10 1809 (versions: < 10.0.17763.8389)
• microsoft / windows 10 21h2 (versions: < 10.0.19044.6937)
• microsoft / windows 10 22h2 (versions: < 10.0.19045.6937)
• microsoft / windows 11 23h2 (versions: < 10.0.22631.6649)
• microsoft / windows 11 24h2 (versions: < 10.0.26100.7781)
• microsoft / windows 11 25h2 (versions: < 10.0.26200.7781)
• microsoft / windows server 2012
• microsoft / windows server 2012 (versions: r2)
• microsoft / windows server 2016 (versions: < 10.0.14393.8868)
• microsoft / windows server 2019 (versions: < 10.0.17763.8389)
• microsoft / windows server 2022 (versions: < 10.0.20348.4711)
• microsoft / windows server 2022 23h2 (versions: < 10.0.25398.2149)
• microsoft / windows server 2025 (versions: < 10.0.26100.32313)
• Microsoft / Windows 10 Version 1607 (versions: 10.0.14393.0)
• Microsoft / Windows 10 Version 1809 (versions: 10.0.17763.0)
• Microsoft / Windows 10 Version 21H2 (versions: 10.0.19044.0)
• Microsoft / Windows 10 Version 22H2 (versions: 10.0.19045.0)
• Microsoft / Windows 11 version 22H3 (versions: 10.0.22631.0)
• Microsoft / Windows 11 Version 23H2 (versions: 10.0.22631.0)

Weakness Classification

• CWE-269

Repositories for Lab Validation (Public Examples)

• nomi-sec/PoC-in-GitHub | stars: 7594 | updated: 2026-03-23 | https://github.com/nomi-sec/PoC-in-GitHub
  Notes: 📡 PoC auto collect from GitHub. ⚠️ Be careful Malware.
• DarkFunct/TK-CVE-Repo | stars: 43 | updated: 2026-03-23 | https://github.com/DarkFunct/TK-CVE-Repo
  Notes: TK-CVE-Repo
• zulloper/cve-poc | stars: 8 | updated: 2026-03-23 | https://github.com/zulloper/cve-poc
  Notes: CVE POC repo 자동 수집기
• fevar54/CVE-2026-21533_Scanner.py | stars: 0 | updated: 2026-03-09 | https://github.com/fevar54/CVE-2026-21533_Scanner.py
  Notes: Este repositorio contiene una herramienta de detección para la vulnerabilidad CVE-2026-21533, una falla de gestión de privilegios en los Servicios de Escritorio Remoto (RDS) de Windows que podría permitir a un atacante local elevar sus privilegios a SYSTEM.

People and Organizations Mentioned

• microsoft
• Windows
• nomi-sec
• DarkFunct
• zulloper
• fevar54

Practical Defensive Validation (Authorized Only)

1. Use only isolated environments and systems you own or are explicitly authorized to test.
2. Snapshot infrastructure before validation and preserve baseline logs (EDR, SIEM, OS, app).
3. Inventory microsoft / windows 10 1607 (versions: < 10.0.14393.8868) assets and confirm exact vulnerable versions with automated checks.
4. Patch in staged environments and validate closure with scanners + service health checks.
5. Map detections to MITRE ATT&CK tactics relevant to your environment and tune alert quality.

References

• NVD record: https://nvd.nist.gov/vuln/detail/CVE-2026-21533
• MITRE CVE record: https://www.cve.org/CVERecord?id=CVE-2026-21533
• CISA KEV Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• CISA KEV JSON feed: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
• KEV notes: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21533 ; https://nvd.nist.gov/vuln/detail/CVE-2026-21533
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21533
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21533
• Repository example: https://github.com/nomi-sec/PoC-in-GitHub
• Repository example: https://github.com/DarkFunct/TK-CVE-Repo
• Repository example: https://github.com/zulloper/cve-poc
• Repository example: https://github.com/fevar54/CVE-2026-21533_Scanner.py

This content is for defensive security training and authorized validation only.