Incorrect Conversion between Numeric Types in Microsoft Windows and Windows Server - CVE-2026-26178

Vulnerability identifier: #VU126134

CSH Severity: High

CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-26178

CWE-ID: CWE-681

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to incorrect conversion between numeric types in Windows Advanced Rasterization Platform. A remote attacker can trick a victim to visit a website or open content that uses WebGL features and gain elevated privileges on the target system.

Microsoft Windows
Windows Server

Install updates from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7184, 10 22H2 10.0.19045.7184, 10 1607 10.0.14393.9060, 10 1809 10.0.17763.8644, 11 23H2 10.0.22631.6936, 11 24H2 10.0.26100.32690, 11 25H2 10.0.26200.8246, 11 26H1 10.0.28000.1836
Windows Server - addressed in versions 2012 R2 6.3.9600.23132, 2016 10.0.14393.9060, 2019 10.0.17763.8644, 2022 23H2 10.0.25398.2274, 2022 10.0.20348.5020, 2025 10.0.26100.32690

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26178

• Privilege escalation in Microsoft Windows Advanced Rasterization Platform