Advisoriesby IbisMicrosoftCVE-2026-83781
Microsoft Windows Program Compatibility Assistant Service: privilege escalation
Fix: upgrade to 10.0.22631.7652 or later (7 fixed versions below)
Improper null termination in Windows Program Compatibility Assistant Service allows an authorized attacker to elevate privileges locally.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Windows 11 Version 23H2 Product | >= 10.0.22631.0, < 10.0.22631.7652 | 10.0.22631.7652 |
| Windows 11 Version 24H2 Product | >= 10.0.26100.0, < 10.0.26100.9711 | 10.0.26100.9711 |
| Windows 11 Version 25H2 Product | >= 10.0.26200.0, < 10.0.26200.9711 | 10.0.26200.9711 |
| Windows 11 Version 26H2 Product | >= 10.0.26300.0, < 10.0.26300.9711 | 10.0.26300.9711 |
| Windows 11 version 23H2 Product | >= 10.0.22631.0, < 10.0.22631.7652 | 10.0.22631.7652 |
| Windows 11 version 26H1 Product | >= 10.0.28000.0, < 10.0.28000.3231 | 10.0.28000.3231 |
| Windows Server 2022 Product | >= 10.0.20348.0, < 10.0.20348.5761 | 10.0.20348.5761 |
| Windows Server 2025 Product | >= 10.0.26100.0, < 10.0.26100.33650 | 10.0.26100.33650 |
| Windows Server 2025 (Server Core installation) Product | >= 10.0.26100.0, < 10.0.26100.33650 | 10.0.26100.33650 |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-170