CVE-2026-123388

HighCVSS 7.8/10Last modified Nov 12, 2026

Description

Heap-based buffer overflow in Windows Program Compatibility Assistant Service allows an authorized attacker to elevate privileges locally.

Metrics

CVSS 3.1 7.8/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-125 CWE-170

Affected software

Source: the vendor's advisory (CNA). NVD analysis pending.

Vendor	Product	Versions
Microsoft	Windows 10 Version 1607	>= 10.0.14393.0, < 10.0.14393.9688
Microsoft	Windows 10 Version 1809	>= 10.0.17763.0, < 10.0.17763.9487
Microsoft	Windows 10 Version 21H2	>= 10.0.19044.0, < 10.0.19044.7846
Microsoft	Windows 10 Version 22H2	>= 10.0.19045.0, < 10.0.19045.7846
Microsoft	Windows 11 version 23H2	>= 10.0.22631.0, < 10.0.22631.7711
Microsoft	Windows 11 Version 23H2	>= 10.0.22631.0, < 10.0.22631.7711
Microsoft	Windows 11 Version 24H2	>= 10.0.26100.0, < 10.0.26100.9974
Microsoft	Windows 11 Version 25H2	>= 10.0.26200.0, < 10.0.26200.9974
Microsoft	Windows 11 version 26H1	>= 10.0.28000.0, < 10.0.28000.3501
Microsoft	Windows 11 Version 26H2	>= 10.0.26300.0, < 10.0.26300.9974
Microsoft	Windows Server 2016	>= 10.0.14393.0, < 10.0.14393.9688
Microsoft	Windows Server 2016 (Server Core installation)	>= 10.0.14393.0, < 10.0.14393.9688
Microsoft	Windows Server 2019	>= 10.0.17763.0, < 10.0.17763.9487
Microsoft	Windows Server 2019 (Server Core installation)	>= 10.0.17763.0, < 10.0.17763.9487
Microsoft	Windows Server 2022	>= 10.0.20348.0, < 10.0.20348.5870
Microsoft	Windows Server 2025	>= 10.0.26100.0, < 10.0.26100.33822
Microsoft	Windows Server 2025 (Server Core installation)	>= 10.0.26100.0, < 10.0.26100.33822

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-123388

Timeline

Published: Nov 10, 2026
Last modified: Nov 12, 2026
NVD status: Awaiting Analysis

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