CVE-2023-21674
Microsoft Windows Advanced Local Procedure Call (ALPC) Privilege Escalation Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 31 January 2023). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 34.21% probability · 98th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Listed 10 January 2023 · due 31 January 2023
- Weakness
- CWE-416
- Affected
- microsoft/windows 10 1507 · microsoft/windows 10 1607 · microsoft/windows 10 1809 · microsoft/windows 10 20h2 · microsoft/windows 10 21h2 · microsoft/windows 10 22h2 · microsoft/windows 11 21h2 · microsoft/windows 11 22h2 · microsoft/windows rt 8.1 · microsoft/windows server 2012 · microsoft/windows server 2016 · microsoft/windows server 2019 · microsoft/windows server 2022
- Source
- secure@microsoft.com
EPSS moved from 34.2% on 25 October 2026 to 34.2% on 30 October 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
CISA notes
Apply updates per vendor instructions. https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-21674; https://nvd.nist.gov/vuln/detail/CVE-2023-21674
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21674Patch, Vendor Advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21674Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-21674US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.