# CVE-2023-21674: Microsoft Windows Advanced Local Procedure Call (ALPC) Privilege Escalation Vulnerability

Source: https://junglewise.ai/threats/cve-2023-21674-microsoft-windows-advanced-local-procedure-call-alpc-privilege  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-01-10. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2023-21674 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2023-01-10

A use-after-free vulnerability in the Windows Advanced Local Procedure Call (ALPC) allows a local attacker to escalate privileges to SYSTEM. The vulnerability is confirmed to have been exploited in the wild.

Technologies: [Microsoft Windows](https://junglewise.ai/threats/technologies/windows). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2023-21674 exploited in the wild?** Yes. CVE-2023-21674 is known to be exploited in the wild, first recorded on 10 January 2023. Treat it as urgent.

**How severe is CVE-2023-21674?** Critical severity, with a CVSS score of 8.8, published 10 January 2023.

**Which products and versions are affected?** Microsoft Windows 10 1507, 1607, 1809, 20H2, 21H2, 22H2; Microsoft Windows 11 21H2, 22H2; Microsoft Windows Server 2012 R2; Microsoft Windows Server 2016; and 3 more.

**Is there a fix for CVE-2023-21674?** A patch was published on 2023-01-10. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2023-21674 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2023-21674?** Check whether you run Microsoft Windows. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Windows 10 1507, 1607, 1809, 20H2, 21H2, 22H2
- Microsoft Windows 11 21H2, 22H2
- Microsoft Windows Server 2012 R2
- Microsoft Windows Server 2016
- Microsoft Windows Server 2019
- Microsoft Windows Server 2022
- Microsoft Windows RT 8.1

## Timeline

- 2023-01-10: disclosed
- 2023-01-10: patched
- 2023-01-10: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2023-01-10: exploited: Reported as exploited in the wild at time of publication.

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