CVE-2023-28216: Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability

CVE-2023-28216 is an elevation of privilege vulnerability in Windows Advanced Local Procedure Call (ALPC), rated Important by Microsoft, with a CVSS 3.1 base score of 7 (High). An attacker can exploit it by an attacker with local access, with low privileges and without user interaction. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 0.37% probability of exploitation activity in the next 30 days, higher than 32% of all scored vulnerabilities. Microsoft released the fix on 11 April 2023 in the April 2023 Patch Tuesday, delivered through 15 security updates (KB5025229, KB5025230, KB5025221, KB5025224 and more). It affects 35 products in 2 product families (Windows, ESU).

Key facts

CVE ID: CVE-2023-28216
Severity: High CVSS 7
Microsoft severity: Important
Impact: Elevation of Privilege
Exploited in the wild: No
Publicly disclosed: No
Exploitation likelihood: Less Likely
EPSS: 0.37% (percentile 32%)
CISA KEV: Not listed
Released: 11 April 2023
Last updated: 11 April 2023
Patch Tuesday: April 2023 Patch Tuesday
Product families: Windows, ESU

CVSS score and vector

Microsoft scores CVE-2023-28216 at 7 (temporal 6.1) using CVSS 3.1. Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Metric	Value
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	High
Exploit code maturity	Unproven
Remediation level	Official fix
Report confidence	Confirmed

Frequently asked questions (Microsoft)

According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?

Successful exploitation of this vulnerability requires an attacker to win a race condition.

What privileges could be gained by an attacker who successfully exploited this vulnerability?

An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Affected products (35)

Windows

Product	Security update	Type	Fixed build	Restart
Windows 10 Version 1809 for 32-bit Systems	KB5025229	Security Update	10.0.17763.4252	Yes
Windows 10 Version 1809 for x64-based Systems	KB5025229	Security Update	10.0.17763.4252	Yes
Windows 10 Version 1809 for ARM64-based Systems	KB5025229	Security Update	10.0.17763.4252	Yes
Windows Server 2019	KB5025229	Security Update	10.0.17763.4252	Yes
Windows Server 2019 (Server Core installation)	KB5025229	Security Update	10.0.17763.4252	Yes
Windows Server 2022	KB5025230	Security Update	10.0.20348.1668	Yes
Windows Server 2022 (Server Core installation)	KB5025230	Security Update	10.0.20348.1668	Yes
Windows 10 Version 20H2 for 32-bit Systems	KB5025221	Security Update	10.0.19042.2846	Yes
Windows 10 Version 20H2 for ARM64-based Systems	KB5025221	Security Update	10.0.19042.2846	Yes
Windows 11 version 21H2 for x64-based Systems	KB5025224	Security Update	10.0.22000.1817	Yes
Windows 11 version 21H2 for ARM64-based Systems	KB5025224	Security Update	10.0.22000.1817	Yes
Windows 10 Version 21H2 for 32-bit Systems
Windows 10 Version 21H2 for ARM64-based Systems
Windows 10 Version 21H2 for x64-based Systems
Windows 11 Version 22H2 for ARM64-based Systems	KB5025239	Security Update	10.0.22621.1555	Yes
Windows 11 Version 22H2 for x64-based Systems	KB5025239	Security Update	10.0.22621.1555	Yes
Windows 10 Version 22H2 for x64-based Systems
Windows 10 Version 22H2 for ARM64-based Systems
Windows 10 Version 22H2 for 32-bit Systems
Windows 10 for 32-bit Systems	KB5025234	Security Update	10.0.10240.19869	Yes
Windows 10 for x64-based Systems	KB5025234	Security Update	10.0.10240.19869	Yes
Windows 10 Version 1607 for 32-bit Systems	KB5025228	Security Update	10.0.14393.5850	Yes
Windows 10 Version 1607 for x64-based Systems	KB5025228	Security Update	10.0.14393.5850	Yes
Windows Server 2016	KB5025228	Security Update	10.0.14393.5850	Yes
Windows Server 2016 (Server Core installation)	KB5025228	Security Update	10.0.14393.5850	Yes

ESU

Product	Security update	Type	Fixed build	Restart
Windows Server 2008 for 32-bit Systems Service Pack 2	KB5025271 KB5025273	Monthly Rollup Security Only	6.0.6003.22015 6.0.6003.22015	Yes Yes
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)	KB5025271 KB5025273	Monthly Rollup Security Only	6.0.6003.22015 6.0.6003.22015	Yes Yes
Windows Server 2008 for x64-based Systems Service Pack 2	KB5025271 KB5025273	Monthly Rollup Security Only	6.0.6003.22015 6.0.6003.22015	Yes Yes
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)	KB5025271 KB5025273	Monthly Rollup Security Only	6.0.6003.22015 6.0.6003.22015	Yes Yes
Windows Server 2008 R2 for x64-based Systems Service Pack 1	KB5025279 KB5025277	Monthly Rollup Security Only	6.1.7601.26466 6.1.7601.26466	Yes Yes
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)	KB5025279 KB5025277	Monthly Rollup Security Only	6.1.7601.26466 6.1.7601.26466	Yes Yes
Windows Server 2012	KB5025287 KB5025272	Monthly Rollup Security Only	6.2.9200.24216 6.2.9200.24216	Yes Yes
Windows Server 2012 (Server Core installation)	KB5025287 KB5025272	Monthly Rollup Security Only	6.2.9200.24216 6.2.9200.24216	Yes Yes
Windows Server 2012 R2	KB5025285 KB5025288	Monthly Rollup Security Only	6.3.9600.20919 6.3.9600.20919	Yes Yes
Windows Server 2012 R2 (Server Core installation)	KB5025285 KB5025288	Monthly Rollup Security Only	6.3.9600.20919 6.3.9600.20919	Yes Yes

Security updates (15)

KB5025229 (Security Update)
KB5025230 (Security Update)
KB5025221 (Security Update)
KB5025224 (Security Update)
KB5025239 (Security Update)
KB5025234 (Security Update)
KB5025228 (Security Update)
KB5025271 (Monthly Rollup)
KB5025273 (Security Only)
KB5025279 (Monthly Rollup)
KB5025277 (Security Only)
KB5025287 (Monthly Rollup)
KB5025272 (Security Only)
KB5025285 (Monthly Rollup)
KB5025288 (Security Only)

NIST NVD data

NVD status: Modified
NVD CVSS: 7 (HIGH)
Published to NVD: 11 April 2023
NVD last modified: 17 June 2026

Affected configurations (CPE)

Product	Vulnerable versions
windows 10 1507	before 10.0.10240.19869
windows 10 1607	before 10.0.14393.5850
windows 10 1809	before 10.0.17763.4252
windows 10 20h2	before 10.0.19042.2846
windows 10 21h2	before 10.0.19044.2846
windows 10 22h2	before 10.0.19045.2846
windows 11 21h2	before 10.0.22000.1817
windows 11 22h2	before 10.0.22621.1555
windows server 2008	all listed versions
windows server 2008 r2 (x64)	all listed versions
windows server 2012	all listed versions
windows server 2012 r2	all listed versions
windows server 2016	all listed versions
windows server 2019	all listed versions
windows server 2022	all listed versions

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-28216 (Patch, Vendor Advisory)
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-28216 (Patch, Vendor Advisory)

Acknowledgments

Microsoft Offensive Research & Security Engineering

Revision history

Version	Date	Description
1.0	11 April 2023	Information published.