SARA / Free Tools / CVE / CVE-2023-21674

CVE-2023-21674 — Microsoft Windows Advanced Local Procedure Call (ALPC) Privilege Escalation Vuln

Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability

CVSS

8.8 HIGH

EPSS

12.43% (top 6.20%)

CWE

CWE-416

Published

2023-01-10T00:00:00.000Z

Last modified

2025-10-21T23:15:28.774Z

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C

CISA KEV — Actively Exploited

Added to KEV

2023-01-10

BOD 22-01 due

2023-01-31

Ransomware use

Unknown

View KEV detail

01What is this vulnerability?

Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability

Vendor	Product	Versions
Microsoft	Windows 10 Version 1809	10.0.17763.0
Microsoft	Windows 10 Version 1809	10.0.0
Microsoft	Windows Server 2019	10.0.17763.0
Microsoft	Windows Server 2019 (Server Core installation)	10.0.17763.0
Microsoft	Windows Server 2022	10.0.20348.0
Microsoft	Windows 10 Version 20H2	10.0.0
Microsoft	Windows 11 version 21H2	10.0.0
Microsoft	Windows 10 Version 21H2	10.0.19043.0
Microsoft	Windows 11 version 22H2	10.0.22621.0
Microsoft	Windows 10 Version 22H2	10.0.19045.0
Microsoft	Windows 10 Version 1507	10.0.10240.0
Microsoft	Windows 10 Version 1607	10.0.14393.0
Microsoft	Windows Server 2016	10.0.14393.0
Microsoft	Windows Server 2016 (Server Core installation)	10.0.14393.0
Microsoft	Windows 8.1	6.3.0
Microsoft	Windows Server 2012 R2	6.3.9600.0
Microsoft	Windows Server 2012 R2 (Server Core installation)	6.3.9600.0

Yes — actively exploited. Added to the CISA KEV catalog on 2023-01-10. Ransomware use: Unknown.

Patch to a fixed version listed in the vendor advisory (see references below).
Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
Hunt historical logs for exploitation indicators — see Detection signatures below.

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

msrc.microsoft.com — https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21674

Want this in your SOAR or SIEM?
SARA's API returns EPSS, CVSS, KEV, and an analyst-grade summary in one call.