CVE-2023-21674
Microsoft Windows Advanced Local Procedure Call (ALPC) Privilege Escalation Vulnerability
Microsoft Windows
Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 10 January 2023. US federal agencies were required to remediate it by 31 January 2023.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 34.2%, which is higher than 98.4% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Frequently asked questions
Is CVE-2023-21674 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2023-21674.
What does CVE-2023-21674 affect?
CVE-2023-21674 affects Microsoft Windows. Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability
How severe is CVE-2023-21674?
CVE-2023-21674 is rated HIGH with a CVSS base score of 8.8. EPSS puts the probability of exploitation in the next 30 days at 34.2%, higher than 98.4% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 31 January 2023.
How should organisations respond to CVE-2023-21674?
Apply the vendor patch for Microsoft Windows as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.